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A study conducted by

RAND Health for the

Medicare Payment Advisory Commission

November 2004 • No.0 4 
WORKING 

P A P E R

SERVICES PROVIDED 

IN MULTIPLE 

AMBULATORY 

SETTINGS: 

A COMPARISON OF SELECTED 

PROCEDURES 

BARBARA O. WYNN 

ELIZABETH M. SLOSS 

CONSTANCE FUNG 

LISA R. SHUGARMAN 

J. SCOTT ASHWOOD 

STEVEN M. ASCH 

WR-160 

July 2004

Prepared for the Medicare Payment Advisory 

Commission

This product is part of the RAND 

Health working paper series. RAND 

working papers are intended to share 

researchers’ latest findings and to 

solicit informal peer review. 

They have been approved for 

circulation by RAND Health, but have 

not been formally edited or peer 

reviewed. 

 

This paper should not be quoted or 

cited without permission of the author. 

RAND’s publications do not 

necessarily reflect the opinions of its 

research clients and sponsors. 

is a registered trademark.
i 

PREFACE 

Technological advances such as improved anesthesia and pain management 

coupled with health care financing changes have produced a shift in services from 

inpatient to outpatient settings and increased the volume and complexity of procedures 

provided in various ambulatory settings. Very little is known about the quality of care 

implications of the shift from inpatient to ambulatory care and how patient and 

procedure characteristics vary among ambulatory settings. 

 The Medicare Payment Advisory Commission (MedPAC) asked RAND to identify 

high-volume services provided in multiple ambulatory settings, such as physicians’ 

offices, hospital outpatient departments (HOPDs), and ambulatory surgical centers 

(ASCs) and to identify measures to examine the feasibility of using administrative data 

to analyze how the nature of a service, the patient characteristics, and outcomes vary 

by the setting in which the service is provided. These analyses are prerequisites for 

evaluating quality and policy issues such as the appropriateness of site-of-service 

payment differentials across ambulatory settings for the same procedure. 

 In this report, we describe the results of our analysis for three selected high 

volume procedures performed in multiple ambulatory settings: magnetic resonance 

(MR) imaging of the head, neck, and brain, cataract surgery, and colonoscopy. Drawing 

on a review of the clinical literature for these procedures that is described in a separate 

report, this research involved an expert panel to rate which measures would be most 

appropriate for investigating variations in these procedures across ambulatory settings. 

We then used Medicare administrative data to investigate the feasibility of examining 

differences in outcomes, patient characteristics, and procedure characteristics across 

multiple ambulatory settings. 

The study findings should be of interest to policymakers interested in Medicare 

payment and quality issues. Health economists and health services researchers may 

also have an interest in the findings. 

This research was sponsored by MedPAC under Contract T-13604561. 

iii 

CONTENTS 

Preface............................................................................................................................. i

Tables ............................................................................................................................. v

Executive Summary .......................................................................................................vii

Methods and Data .............................................................................................. viii

Results ............................................................................................................... viii

Expert Panel......................................................................................................... x

Empirical Evaluation .............................................................................................xi

Acknowledgments ..........................................................................................................xv

Glossary ....................................................................................................................... xvii

1. Overview .................................................................................................................... 1

Overview of Study ................................................................................................ 1

Medicare Site of Service Requirements ............................................................... 3

Payment Incentives .............................................................................................. 5

Organization of This Report.................................................................................. 6

2. Expert Panel Process.................................................................................................. 7

Overview of the Expert Panel Process ................................................................. 7

Preventability and Severity of Outcomes.............................................................. 9

Patient Characteristics........................................................................................ 10

Procedure Characteristics .................................................................................. 11

3. Empirical Evaluation of Measures ............................................................................ 15

Data Sources...................................................................................................... 15

File Construction................................................................................................. 16

Statistical Analysis.............................................................................................. 18

4. MRI of Head, Neck, and Brain.................................................................................. 21

Expert Panel Results .......................................................................................... 21

Patient Characteristics.................................................................................... 22

Procedure Characteristics .............................................................................. 22

Outcomes ....................................................................................................... 23

Empirical Evaluation Results .............................................................................. 23

Procedure Characteristics .............................................................................. 24

Patient Characteristics.................................................................................... 30

Outcomes ....................................................................................................... 31

Summary of Findings.......................................................................................... 35

5. Cataract Surgery ...................................................................................................... 37

Expert Panel Results .......................................................................................... 37

Patient Characteristics.................................................................................... 38

Procedure Characteristics .............................................................................. 38

Outcomes ....................................................................................................... 39

Empirical Evaluation ........................................................................................... 39
iv 

Procedure Characteristics .............................................................................. 39

Patient Characteristics.................................................................................... 45

Outcomes ....................................................................................................... 46

Summary of Findings.......................................................................................... 47

6. Colonoscopy ............................................................................................................ 53

Expert Panel Results .......................................................................................... 53

Patient Characteristics.................................................................................... 54

Procedure Characteristics .............................................................................. 54

Outcomes ....................................................................................................... 55

Empirical Evaluation Results .............................................................................. 55

Procedure Characteristics .............................................................................. 58

Patient Characteristics.................................................................................... 60

Outcomes ....................................................................................................... 64

Summary of Findings.......................................................................................... 65

7. Summary of Findings and Discussion ..................................................................... 67

Summary of findings for study procedures ......................................................... 67

Discussion .......................................................................................................... 69

Expert Panels ................................................................................................. 69

Empirical Evaluation....................................................................................... 70

Appendix A. HCPCS (CPT) Codes for Three Study Procedures.................................. 77

BETOS I2C: Advanced imaginG—MRI: head, neck, and brain .......................... 77

BETOS P4B: Eye procedure—cataract removal/lens insertion .......................... 78

BETOS P8D: Endoscopy—colonoscopy ............................................................ 79

Appendix B. Expert Panel for MRI of Brain, Head and Neck........................................ 81

MRI Rating Forms and Expert Panel Process .................................................... 82

Summary of MRI Expert Panel Ratings for Patient Characteristics .................... 83

Summary of MRI Expert Panel Ratings for Procedure Characteristics............... 87

Summary for MRI Expert Panel Ratings for Patient Outcomes .......................... 88

Appendix C. Expert Panel on Cataract Surgery ........................................................... 89

Cataract Rating Forms and Expert Panel Process ............................................. 90

Summary of Cataract Expert Panel Ratings for Patient Characteristics ............. 91

Summary of Cataract Expert Panel Ratings for Procedure Characteristics........ 94

Summary of Cataract Expert Panel Ratings for Patient Outcomes..................... 95

Summary of Cataract Expert Panel Ratings for Patient Outcomes..................... 96

Appendix D. Expert Panel on Colonoscopy.................................................................. 97

Colonoscopy Rating Forms and Expert Panel Process ...................................... 98

Summary of Colonoscopy Expert Panel Ratings for Patient Characteristics ...... 99

Summary of Colonoscopy Expert Panel Ratings for Procedure Characteristics104

Summary of Colonoscopy Expert Panel Ratings for Patient Outcomes ........... 109

REFERENCES............................................................................................................ 111
v 

TABLES 

Table 2.1 List of Organizations Contacted for Expert Panel............................................ 8

Table 2.2 Definition and Scale Used to Rate Preventability and Severity ....................... 9

Table 2.3 Example of Line Item from Initial Round Rating Summary for Outcome 

Section of the Cataract Panel Rating Form........................................................... 10

Table 2.4 Example of Line Item for Patient Characteristic Section of Cataract 

Rating Form .......................................................................................................... 11

Table 2.5 Illustration of Line Item for Procedure Characteristics Section of 

Cataract Rating Form............................................................................................ 13

Table 4.1 Characteristics of Beneficiaries with MRI of Head, Neck, Brain 

(BETOW 12C) By Ambulatory Setting, Medicare Fee-for-Service System, 

2001 ...................................................................................................................... 25

Table 4.2 Percentage of MRI of Head, Neck, and Brain (BETOS 12C) Preformed 

In Three Ambulatory Settings, Medicare Fee-for-Service, 2001 ........................... 26

Table 4.3 Distribution of MRI Head, Neck, and Brain (BETOS 12C) by HCPCS 

and Number of Procedures Coded for Same Day By Ambulatory Setting, 

Medicare Fee-for-Service System, 2001............................................................... 27

Table 4.4 Top five Specialties* of Providers Performing MRI of Head, Neck, and 

Brain (BETOS 12C) By Ambulatory Setting, Medicare Fee-for-Service 

System, 2001 ........................................................................................................ 29

Table 4.5 Average Risk Scores for Beneficiaries With MRI of Head, Neck, and 

Brain (BETOS 12C) By Ambulatory Setting, Medicare Fee-for-Service 

System, 2001 ........................................................................................................ 30

Table 4.6 Top Ten Diagnoses on Facility Claim* for MRI of Head, Neck, and 

Brain (BETOS 12C) By Ambulatory Setting, Medicare Fee-for-Service, 2001 ...... 32

Table 4.7 Selected Risk Factors of Beneficiaries With MRI of Head, Neck, and 

Brain (BETOS 12C) By Ambulatory Setting, Medicare Fee-for-Service 

System, 2001 ........................................................................................................ 33

Table 4.8 Selected Adverse outcomes Occurring Within 30 Days Following MRI 

of Head, Neck, and Brain (BETOS 12C) By Ambulatory Setting, Medicare 

Fee-for-Service System, 2001............................................................................... 34

Table 5.1 Characteristics of Beneficiaries With Cataract Surgery (BETOS P4B) 

By Ambulatory Setting, Medicare Fee-for-Service, 2001 ...................................... 41

Table 5.2 Percentage of Cataract Surgeries (BETOS P4B) Performed In Three 

Ambulatory Settings By Geographic Area, Medicare Fee-for-Service 

System, 2001 ........................................................................................................ 42

Table 5.3 Distribution of Cataract Surgeries (BETOS P4B)* By HCPCS and 

Number of Procedures Coded for Same Day By Ambulatory Setting, 

Medicare Fee-for-Service, 2001............................................................................ 43
vi 

Table 5.4 Top Five Specialties* of Providers Performing Cataract Surgery 

(BETOS P4B) By Ambulatory Setting, Medicare Fee-for-Service System, 

2001 ...................................................................................................................... 44

Table 5.5 Anesthesia Services Related to Cataract Surgery By Ambulatory 

Setting, Medicare Fee-for-Service System, 2001.................................................. 45

Table 5.6 Average Risk Scores With Cataract Surgery (BETOS P4B) By 

Ambulatory Setting, Medicare Fee-for-Service System, 2001............................... 48

Table 5.7 Top Ten Diagnoses on Facility Claim* for Cataract Surgery (BETOS 

P4B) By Ambulatory Setting, Medicare Fee-for-Service System, 2001................. 49

Table 5.8 Selected Risk Factors of Beneficiaries With Cataract Surgery (BETOS 

P4B) By Ambulatory Setting, Medicare Fee-for-Service System, 2001................. 50

Table 5.9 Selected Outcomes Occurring Within 30 Days Following Cataract 

Surgery (BETOS P4B) By Ambulatory Setting, Medicare Fee-for-Service 

System, 2001 ........................................................................................................ 51

Table 6.1 Characteristics of Beneficiaries with Colonoscopy (BETOS P8D) By 

Ambulatory Setting, Medicare Fee-for-Service System, 2001............................... 56

Table 6.2 Percentage of Colonoscopies (BETOS P8D) Performed in Three 

Ambulatory Settings By Geographic Area, Medicare Fee-for-Service, 2001......... 57

Table 6.3 Distribution of Colonoscopies (BETOSP8D) and Number of Procedures 

Coded for Same Day By Ambulatory Setting, Medicare Fee-for-Service, 

2001 ...................................................................................................................... 59

Table 6.4 Top Five Specialties* of Providers Performing Colonoscopy (BETOS 

P8D) By Ambulatory Setting, Medicare Fee-for-Service System, 2001 ................ 60

Table 6.5 Average Risk Scores for Beneficiaries With Colonoscopies (BETOS 

P8D) By Ambulatory Setting, Medicare Fee-for-Service, 2001 ............................. 62

Table 6.6 Top Ten Diagnoses on Facility Claim for Colonoscopy (BETOS P8D) 

By Ambulatory Setting, Medicare Fee-for-Service System, 2001 ......................... 62

Table 6.7 Selected Risk Factors of Beneficiaries With Colonoscopy (BETOS 

P8D) By Ambulatory Setting, Medicare Fee-for Service System, 2001................. 63

Table 6.8 Selected Outcomes Occurring Within 30 Days Following Colonoscopy 

(BETOS P8D) By Ambulatory Setting, Medicare Fee-for-Service System, 

2001 ...................................................................................................................... 64
vii 

EXECUTIVE SUMMARY 

While ambulatory procedures can be performed in a variety of settings, most are performed 

in three settings: hospital outpatient departments (HOPDs), ambulatory surgical centers (ASCs,) 

and physician offices. Technological advances such as improved anesthesia and pain 

management coupled with health care financing changes have produced a shift in services from 

inpatient to outpatient settings and increased the volume and complexity of procedures provided 

in ambulatory settings. Very little is known about the quality of care implications of the shift from 

inpatient to ambulatory care and how patient and procedure characteristics vary among 

ambulatory settings. 

 The Medicare Payment Advisory Commission (MedPAC) asked RAND to identify highvolume services provided in multiple ambulatory settings, such as physicians’ offices, HOPDs, 

and ASCs and to identify measures to examine the feasibility of using administrative data to 

analyze how the nature of a service, the patient characteristics, and outcomes vary by the setting 

in which the service is provided. These analyses are prerequisites for evaluating quality and 

policy issues such as the appropriateness of site-of-service payment differentials across 

ambulatory settings for the same procedure. 

 In this report, we describe the results of our analysis for three selected procedures: 

magnetic resonance (MR) imaging of the head, neck, and brain, cataract surgery, and 

colonoscopy. MedPAC selected the study procedures in consultation with RAND. Together, the 

procedures account for about 2.4 percent of the volume and 17.0 percent of payments for 

diagnostic and therapeutic procedures in ambulatory settings exclusive of evaluation and 

management services, professional anesthesia services, outpatient rehabilitation therapy services 

and laboratory tests1. Drawing on the results of a literature review, the study involved both an 

expert panel to rate which measures would be most appropriate for investigating variations in 

these procedures across ambulatory settings and analyses of Medicare administrative data. 

 1 This calculation does not include DME, drugs and medical supplies, and outpatient dialysis and accounts only for 

professional and facility services provided in physician offices, ASCs, HOPDs, and IDTFs. 
viii 

METHODS AND DATA 

We conducted three expert panel meetings, one for each of the selected procedures. We 

used a modified version of the RAND appropriateness method for the expert panel process (Fitch 

et al., 2001). Generally, the method quantitatively assesses the expert judgments of a group of 

clinical experts by using a rating scale ranging from 1 to 9 and a measure of dispersion. Panelists 

were asked to rate the study procedure on several dimensions: the preventability and severity of 

selected adverse outcomes, patient characteristics that might affect where care is delivered, and 

procedure characteristics that might affect the appropriateness of furnishing the services in 

particular settings to patients at different risk levels. 

After the expert panel ratings were compiled, we tested the feasibility of using 

administrative data to measure differences among the ambulatory settings using 2001 claims data 

for Medicare fee-for-service beneficiaries. The objectives of these analyses were: 

• To examine the extent to which the patient population receiving a procedure and/or the 

nature of the procedures within that grouping varied by setting. 

• To assess the feasibility of identifying complications and adverse outcomes that might 

occur during or after a procedure using administrative data. 

• To identify variables in the administrative data that differentiate characteristics of the 

service. 

RESULTS 

MRI of the brain. On the issue of patient characteristics, the panel ratings and discussion 

indicated that MRIs are low risk procedures that can be safely performed in the different 

ambulatory settings. The two conditions that might pose risk- acute myocardial infarction (AMI) 

within the past seven days and automatic implantable cardioverter defibrillator (AICD) implants - 

were thought to occur very infrequently and this was confirmed by the empirical evidence. The 

expert panel discussed the issue of generalizability briefly and indicated that it is likely that similar 

results would be obtained from panels discussing other MRI and magnetic resonance angiography 

(MRA) procedures, with and without contrast materials. 

The empirical data indicated that patients receiving MRI with contrast have higher average 

HCC risk scores than patients receiving MRI without contrast, suggesting that they are more 
ix 

medically complex patients.2 However, after controlling for use of contrast media, the pattern of 

HCC risk scores across the sites is inconsistent. The data indicate that a higher proportion of 

MRIs with contrast are performed in HOPDs than in community settings. Both general medical 

outcomes and procedure-specific outcomes occurred at a low rate in all three ambulatory settings 

following MRI, but differences across the sites are measurable. For all MRIs (with and without 

contrast), the rates for most outcomes were highest in the office setting. The HOPD rates were 

slightly lower than rates in the office and the rates for IDTFs were considerably lower. 

Cataract Surgery. About 97 percent of procedures within this BETOS category were for a 

single HCPCS code. Detecting differences in this procedure across settings is problematic 

because of billing requirements for anesthesia time and materials and bundling of intraocular 

lenses into the facility payment. On the issue of patient characteristics, the panel ratings and 

discussion indicated that these are low risk procedures that can be safely performed in either an 

HOPD or ASC. Nevertheless, there are differences in the patient characteristics. The average 

HCC risk score is higher among patients having cataract surgery in an HOPD (1.21) than an ASC 

(1.14) and the prevalence rates for at-risk conditions are consistently higher for all 17 risk factors 

among patients having the cataract surgery in an HOPD than in an ASC. Adverse outcomes 

occurred at a low rate following cataract surgery. The analyses found few cataract procedures 

were performed in physician offices, but the findings for these procedures suggest that further 

investigation might be warranted. It is difficult to assess how likely these patterns would be to 

persist in other minor ophthalmologic and non-ophthalmologic surgical procedures. 

Colonoscopy. Compared to physician offices, a higher proportion of procedures performed 

in HOPDs and ASCs involve some lesion removal, biopsy, or control of bleeding. On the issue of 

patient characteristics, the panel did not reach agreement on the appropriateness of physician 

offices as the site of care for several types of colonoscopies. Among the patient characteristics 

that might increase risk, the prevalence rates are higher among patients having the colonoscopy 

in an HOPD than in an ASC. Although based on extremely small numbers, the prevalence rates 

of several risk factors are higher among the patients having colonoscopy in the office than in the 

HOPD. Looking at all colonoscopies combined, the average HCC risk score for those performed in 

the HOPD (1.08) is higher than those in an office (1.04) or an ASC (1.00). All adverse outcomes 

 2 The hierarchical condition category (HCC) risk adjustment model assigns a risk score based on a beneficiary’s expected 

service use given their demographic characteristics (age, sex, etcetera) and medical conditions relative to that of the national average 

beneficiary. It can be used to identify patients who are likely to have complex medical needs.
x 

following colonoscopy occurred at a very low rate in all three ambulatory settings with only four 

with rates above 10 per 1000 (abdominal pain, chest pain, shortness of breath, and hemorrhage). 

The panel and RAND clinical project staff thought these risk patterns would likely be similar for 

other elective endoscopic procedures. 

EXPERT PANEL 

Several crosscutting themes emerged from the panel discussions and ratings that merit 

highlighting: 

• The three study procedures were low-risk procedures that for most patients are 

appropriately performed across different ambulatory sites as long as the site has properly 

trained staff and appropriate equipment. There were only a few instances (e.g., MRI with 

anesthesia or high dose contrast media) in which the panelists agreed it might be 

inappropriate to furnish the service in community-based settings. The colonoscopy panel 

was divided on the appropriateness of performing more complex procedures on higher risk 

patients in office settings. 

• While Medicare has different health and safety standards for hospitals, ASCs, physician 

offices and IDTFs, it is not clear whether these have implications for how care is delivered 

across these settings. An off-campus hospital outpatient surgery center may be more like a 

freestanding ASC than the hospital-affiliated ASC that is co-located on the hospital’s main 

campus. Differences between the typical care processes, physician specialties and 

equipment in an IDTF compared to a physician office are not well understood. State 

licensure laws and accreditation may be important factors in understanding the differences. 

For example, several panelists at the colonoscopy panel argued that some state licensure 

laws require that a physician office performing colonoscopies “look like an ASC” and should 

not be rated based on a typical physician office. The division among the panel members 

over the appropriateness of furnishing particular colonoscopies in physician offices may be 

indicative of different perceptions of the structural characteristics of physician offices where 

colonoscopies are performed. 
xi 

• Risk is higher for procedures that require general anesthesia or, for example, high dose 

contrast media. A MRI panelist noted that the Joint Commission on Accreditation of 

Healthcare Organizations (JCAHO) had stringent monitoring requirements for the 

administration of contrast media that might have both cost and quality implications relative 

to non-JCAHO accredited facilities. 

• We asked during the panel meetings whether there were particular patient subgroups that 

might require additional resources. Each panel provided specific examples but no ratings 

were solicited on the examples. For example, the MRI panel indicated a patient with 

claustrophobia was more time-consuming and may require sedatives. Only one or two 

examples were identified in each panel meeting and the three panels did not identify the 

same general health conditions. 

• The generalizability of the findings to other procedures varied. Panelists felt that the risk 

patterns elucidated for MRI would likely apply to other MRI and MRA procedures, even 

though they did not formally evaluate this. Similarly the patterns observed for colonoscopy 

would likely apply to other elective endoscopic procedures, though the underlying patients 

characteristics would likely have very different distributions. The cataract panelists found it 

difficult to ascertain how other minor ophthalmologic procedures would compare to their 

findings. 

EMPIRICAL EVALUATION 

The second component of this task was to apply a set of clinically based measures to the 

claims data for a 5 percent sample of Medicare beneficiaries. Using claims data to examine 

potential differences in quality and processes of care across ambulatory settings has several 

advantages. Medicare claims data are routinely collected, available relatively quickly, and are 

relatively inexpensive to analyze. However, outcomes can be difficult to measure using 

administrative data because clinical detail is lacking and data elements not directly related to 

payment might be unreliable. 

Using administrative data to examine the study questions involved complex matching of 

provider and professional claims that had different formats, variables, and reporting requirements. 
xii 

In the process of matching the facility and professional claims, we were able to match a much 

higher proportion of records using the beneficiary ID, date of service, and the BETOS code rather 

than using beneficiary ID, date of service, and the HCPCS code. This indicates that the HCPCS 

procedure code on the facility claim frequently differs from the HCPCS code on the professional 

claim and could complicate procedure-specific analyses.3 

There are also concerns about using claims data for condition-specific analyses because 

identifying clinical subgroups of patients with ICD-9-CM codes might be problematic. The 

nomenclature provides only limited indicators of the severity of a condition. This makes identifying 

specific clinical outcomes following a procedure difficult. For example, the colonoscopy panel 

noted that some complications could range from minor to severe. Concerned with the potential 

under-reporting of complications, the panel rated complications with the understanding that only 

those that are severe are likely to be found in the administrative data. Hospitals tend to report 

more diagnosis codes in administrative data than community-based settings, which is likely to bias 

cross-site comparisons. 

Attributing outcomes to particular procedures requires the tenuous assumption of causality. 

Both the cataract and MRI panels expressed concern that conditions following the procedure may 

be more indicative of ineffective or poor pre-or post-operative care rather than being complications 

related to the actual procedure. In their ratings, the cataract panel limited the more general health 

outcomes to those occurring within 7 days compared to a 30-day window for eye-specific 

complications. Using bleeding as an example, the colonoscopy panel also cautioned that it might 

be difficult to distinguish a potential complication of the colonoscopy from the underlying 

symptoms that created the need for the procedure. 

In these preliminary analyses, we controlled for major procedure differences that might 

affect outcomes by separately examining complication rates for MRI with and without contrast 

media and colonoscopy with and without lesion removal, biopsy, or control of bleeding. (Cataract 

surgeries were dominated by one procedure code). However, we did not control for differences in 

patient characteristics across settings that might affect outcomes. For example, the cataract panel 

suggested it would be important to look at rates for cystoid macular edema separately for diabetic 

and non-diabetic patients since diabetes make the condition less preventable. For congestive 

 3 The Berenson-Eggers Type of Service (BETOS) classification is used to group clinically similar HCPCS procedure 

codes. The study procedures by HCPCS and BETOS codes are listed in Appendix A. 
xiii 

heart failure, the panelists suggested that the analysis should look for signs of new or worsening 

congestive heart failure. These are the types of refinements that would need to be made before 

any conclusions could be made concerning differences in outcomes across ambulatory settings. 

One study question was whether there are differences in the nature of the procedure in 

different settings. Other than differences that are accounted for by the HCPCS codes and 

modifiers that affect payment (such as whether the surgeon performing cataract surgery also 

provided the pre- and post-operative care), we found our ability to address this issue through the 

administrative data was limited. Modifier codes that we thought might have some potential (such 

as those for interrupted procedure and unusual services) are used infrequently, and their actual 

use is as likely to reflect coding practices as procedure differences. Moreover, the “unusual 

services” modifier is in relation to the provider’s typical procedure rather than a normative 

standard and, for example, cannot be used to compare the number of sequences in an MRI. We 

were not able to use the anesthesia claims to assess whether there are differences in the length 

of surgical procedures and, because of match rates, results concerning type of anesthesia are 

also problematic. Finally, the opportunity to examine product differences was also affected by the 

different payment rules for ambulatory services. For example, we were unable to compare 

anesthetics across the settings because the anesthetic is bundled into the ASC and HOPD facility 

payments. One distinction between HOPDs and the other ambulatory settings is that resident 

training, which may increase the amount of time required to perform the procedure, takes place 

almost exclusively in HOPD settings. 

A related study question was whether administrative data could be used to determine if 

there are differences in the patient characteristics across the three settings that might affect the 

resources required to perform the procedure. Enrollment data provide beneficiary-level information 

on patient demographics (age, sex, race) and factors that might affect the medical complexity of a 

patient (Medicaid status, entitlement based on disability or end-stage renal disease). The claims 

history also provides a mechanism to identify patients with particular conditions requiring medical 

care subject to the limitations discussed above regarding the use of ICD-9-CM codes. The claims 

history can also be used to assign patients to HCC risk categories that can be used to summarize 

the patient’s medical complexity based on predicted needs. The underlying assumption is that 

performing a diagnostic or surgical procedure on a medically complex patient or patient with a 
xiv 

particular condition such as dementia may require more resources; however, this is an empirical 

question that cannot be answered directly with administrative data. 

The overall limitations of claims data and of specific variables used in our analysis do not 

mean that claims data should not be used for clinically-based measures, though confirmation with 

more clinically detailed methods such as chart review would be desirable. The expert panel 

ratings and our preliminary empirical analyses for the three procedures suggest that with further 

refinement the administrative data can be used to reach a number of policy-relevant conclusions 

that have implications not only for the study procedures but also for other procedures with similar 

characteristics. 
xv 

ACKNOWLEDGMENTS 

We are grateful for the valuable support we received throughout this project from our 

Project Officers at MedPAC, Ariel Winter and Chantal Worzala. They ensured that we had access 

to the data we needed to conduct the study and provided insightful analytic comments throughout 

the research and on an earlier version of this report. We are also indebted to the members of our 

expert panels, whose names and affiliations are provided in the appendices. In addition, Dr. Peter 

Chen provided helpful clinical input in preparation for the expert panels. We would like to thank 

Landon Donsbach and Donna White for the administrative support they provided for the expert 

panels. We would also like to express our appreciation to Ellen Singer, Arlene Turner and Valerie 

Bakaushin of Social and Scientific Systems for the programming support they provided in 

generating the listings of high volume ambulatory procedures and the analytic files for the study 

procedures. 

xvii 

GLOSSARY 

Symbol Definition 

AICD 

AMI 

APC 

ASC 

CMS 

COPD 

CRNA 

DRG 

HCC 

HOPD 

ICD-9 

CM 

IDTF 

MedPAC 

MRA 

MRI 

MTUS 

RBC 

SAF 

SSS 

Automatic implantable cardioverter defibrillator 

Acute myocardial infarction 

Ambulatory Payment Classification 

Ambulatory surgical center 

Centers for Medicare and Medicaid Services 

Chronic obstructive pulmonary disease 

Certified Registered Nurse Anesthetist 

Diagnosis-related group 

Hierarchical Condition Category 

Hospital outpatient department 

International Classification of Disease, 9th Revision, 

Clinical Modification 

Independent diagnostic testing facility 

Medicare Payment Advisory Commission 

Magnetic resonance angiography 

Magnetic resonance imaging 

Miles, Time; Units, Services Count 

Removal, biopsy, or control of bleeding 

Standard Analytic File 

Social and Scientific Systems, Inc. 
1 

1. OVERVIEW 

While ambulatory procedures can be performed in a variety of settings, most are performed 

in three settings: hospital outpatient departments (HOPDs), freestanding ambulatory surgical 

centers (ASCs), and physician offices. Other settings include freestanding independent diagnostic 

testing facilities (IDTFs), community health centers, and rural health clinics. Technological 

advances such as improved anesthesia and pain management coupled with health care financing 

changes have produced a shift in services from inpatient to outpatient settings and increased the 

volume and complexity of procedures provided in ambulatory settings. Very little is known about 

the quality of care implications of the shift from inpatient to ambulatory care and how outcomes 

and patient and procedure characteristics vary across ambulatory settings. 

In this section, we summarize the purpose of our study examining services provided in 

ambulatory settings, discuss the organization of this report, and provide an overview of Medicare 

coverage and payment policies related to ambulatory services. 

OVERVIEW OF STUDY 

The Medicare Payment Advisory Commission (MedPAC) asked RAND to identify highvolume services provided in multiple ambulatory settings, such as physicians’ offices, HOPDs, 

and ASCs and to examine the feasibility of using administrative data to analyze how the nature of 

a service, the patient population, and outcomes vary by the setting in which the service is 

provided. These analyses are prerequisites for evaluating quality and policy issues such as the 

appropriateness of site-of-service payment differentials across ambulatory settings for the same 

procedure.4 They address a limited set of preliminary questions: 

1. Which procedures are provided in more than one ambulatory setting? Which of these are 

high volume? 

 4 While the issue of when care is provided appropriately in an inpatient vs. outpatient setting remains an important 

issue, the study focus is on the variations in procedures performed in ambulatory settings. Medicare site of service payment 

differentials for ambulatory procedures may adversely affect beneficiary access to appropriate care or the efficient delivery 

of needed health care services.
2 

2. Does the medical literature identify the conditions under which certain procedures should 

be provided in a particular setting or indicate outcomes for particular types of patients are 

sensitive to where a certain procedure is performed? 

3. What outcomes and indicators that can be monitored with administrative data might be 

used to assess differences in patient characteristics and the processes and quality of care 

across ambulatory settings for certain procedures? 

Our study has involved three sequential tasks. In the initial task, RAND, in conjunction with 

MedPAC and Social and Scientific Systems, Inc., used Calendar Year 2001 Medicare Part B 

claims data for a 5% beneficiary sample to identify high volume procedure groupings provided in 

at least two of four ambulatory settings: ASCs, HOPDs, physician offices, and IDTFs. 

MedPAC, in consultation with RAND, then reviewed the high volume procedures to select 

three procedures for further study. The high volume procedures that were considered potential 

candidates for further study met two basic criteria: 

• the procedure was performed in at least two sites of care (>10% of total volume in each 

site); and, 

• the procedure was among the top 25 multi-site procedures in terms of total volume or 

expenditures 

The objective was to choose a diverse set of high volume study procedures that vary by type (e.g., 

surgical vs. non-surgical), potential safety concerns, and to include at least the three main 

ambulatory care settings in the study. The three procedures selected for further study were: 

magnetic resonance imaging (MRI) of the head, neck, and brain, cataract surgery, and 

colonoscopy. This set of procedures represents much of the range of issues at the intersection of 

patient safety and procedure venue for Medicare outpatient procedures. Together, the procedures 

account for about 2.4 percent of Medicare’s volume and 17 percent of its of payments for 

diagnostic and therapeutic procedures in ambulatory settings exclusive of evaluation and 

management services, professional anesthesia services, outpatient rehabilitation therapy services 
3 

and laboratory tests5. When only those procedures performed in multiple ambulatory settings (i.e., 

at least 10 percent of the time in two different settings) are considered, the procedures represent 

about 3.4% of Medicare’s volume and 20.4 % of its payments. 

The second task was an in-depth literature review for the three high-volume procedures 

selected for further study. The literature review focused on research related to outcome and 

process indicators for the study procedures, including any studies on the relationship between the 

setting and patient characteristics, processes of care, and outcomes. The literature reported fairly 

consistently the set of process measures and major and minor complications for cataract surgery 

and colonoscopies but only one paper reported process measures for MRI. The literature that we 

reviewed on each of the three procedures was generally silent on the issue of differences in 

patient characteristics, process measures, and outcomes of care across settings of care. In 

general, the literature did not address positive outcomes of care and only a small subset of studies 

examined the patient characteristics associated with complications of care. The findings from the 

literature review are reported separately in LShugarman, CFung, HLopez, and BWynn, Services 

Provided In Multiple Ambulatory Settings: A Review Of The Literature For Selected Procedures 

(2004). 

The third and final task, which is the subject of this report, was to explore the feasibility of 

using administrative data to measure the quality and process indicators and to evaluate the extent 

to which the patient population and/or the nature of the service within the study procedure 

groupings vary by setting. Drawing on the results of the literature review, the task involved both 

expert panels to rate which measures would be most appropriate for investigating variations in 

these procedures across ambulatory settings and analyses of Medicare administrative data. 

 MEDICARE SITE OF SERVICE REQUIREMENTS 

 To participate in the Medicare program, hospitals must meet health and safety standards 

established by the Centers for Medicare and Medicaid Services (CMS) and any state licensure 

requirements. Hospitals accredited by the Joint Commission on Accreditation of Healthcare 

Organizations are deemed to meet these requirements. For coverage and payment purposes, 

Medicare does not distinguish between clinics and other outpatient facilities that are co-located 

 5 This calculation does not include DME, drugs and medical supplies, and outpatient dialysis and accounts only for 

professional and facility services provided in physician offices, ASCs, HOPDs, and IDTFs. 
4 

with the hospital’s inpatient services and those that are clinically and financially integrated with the 

hospital but located off-site. As long as Medicare’s conditions of participation and criteria for 

“provider-based” designation are met, the off-site facility can furnish the same constellation of 

services and receive the same payment as an on-campus outpatient department. 

Freestanding ASCs are also required to meet CMS health and safety standards as well as 

any applicable state licensure requirements. By definition, an ASC is primarily organized to 

provide facility services instead of physician or other practitioner services. ASCs must have 

emergency equipment and personnel trained in its use and an effective process for immediately 

transferring to a hospital any patient who requires emergency medical care beyond the ASC’s 

capabilities. Medicare pays the ASC for facility services and pays separately for physician 

services provided in ASCs. Restrictions on the procedures that are eligible for an ASC facility fee 

are intended to ensure patient safety as well as to encourage the movement of procedures from 

inpatient settings and to preclude a shift of services from physician offices. Procedures on the list 

of approved ASC procedures generally meet the following clinical and safety criteria: 

• The time needed to perform the procedure should not exceed 90 minutes of surgery time or 

four hours of recovery time. Anesthesia time should be less than 90 minutes. 

• The procedure should not generally result in extensive blood loss, require major or 

prolonged invasion of body categories, directly involve major blood vessels, or be generally 

emergent or life threatening. 

Payment rules for services performed in a physician’s office apply when an ASC furnishes 

services that are not on the approved list of ASC procedures. While there are no coverage 

limitations on where physician professional services may be performed, there are no non-facility 

practice expense relative values for surgical services that are essentially performed only in facility 

settings. For example, there are no non-facility practice expense RVUs for cataract surgery 

because this procedure is performed in an office setting only a very small percentage of the time. 

CMS has established rules regarding the level of physician supervision required for 

particular diagnostic tests performed in non-hospital settings.6 These levels are: 

 6 Physician supervision is assumed for hospital outpatient services. 
5 

• General supervision. The procedure is performed under the physician’s overall direction 

and control but the physician’s presence is not required while the procedure is being 

performed. 

• Direct supervision. The physician must be present in the office suite and immediately 

available to furnish assistance and direction while the procedure is performed. 

• Personal supervision. The physician must be in attendance in the room during the 

performance of the procedure. 

MRIs of the head, neck, and brain that involve contrast material require direct supervision 

by a physician while those that do not involve contrast material require only general supervision. 

Personal supervision is not required for any MRIs of the head, neck, or brain. 

CMS defines an independent diagnostic testing facility (IDTF) as a fixed location, mobile 

entity, or individual non-physician practitioner that provides diagnostic procedures independent of 

a physician's office or hospital. For coverage and payment purposes, IDTFs are treated as 

physician offices and the level of supervision requirement for a diagnostic test in a physician’s 

office also applies to an IDTF. The IDTF must have one or more supervising physicians who 

evidence proficiency in the performance and interpretation of each type of diagnostic procedure 

performed by the IDTF and provide ongoing oversight. Non-physician personnel used by the 

IDTF must demonstrate the basic qualifications to perform the tests and be licensed (or accredited 

by an appropriate national accrediting body in the absence of a state licensure requirement). 

PAYMENT INCENTIVES 

Medicare’s coverage of ASC procedures beginning in 1982, implementation of the 

Medicare prospective payment system for acute care inpatient hospital services in 1983, and the 

growth of Medicare managed care have created financial incentives to shift services to ambulatory 

settings. More recently, different Medicare payment amounts for the facility component of 

ambulatory procedures (that is, the prospective payments for hospital outpatient services, the 

ASC facility rate, and the practice expense component of the physician fee schedule) have raised 

concerns that financial incentives could influence the choice of ambulatory setting and affect 

beneficiary access and quality of care as well as Medicare expenditures. The differentials are 

caused by the payment systems for each setting: 
6 

• A prospective payment system for hospital outpatient services was implemented in August 

2000 that uses an Ambulatory Payment Classification (APC) system to group clinically 

coherent sets of procedures that require similar resources. A prospective payment rate for 

each APC is based on the median cost for the procedures in the group relative to a midlevel clinic visit. 

• Medicare pays ASCs for approved ambulatory surgery procedures using 9 payment 

groups. Rates for these groups are based on facility overhead expenses and procedurespecific charges from a 1986 ASC survey with periodic adjustments for intervening inflation. 

• The practice expense component of the physician fee schedule is based on resourcebased relative values that take into account employee wages, rent, and equipment and 

supply costs incurred in performing a procedure. The practice expense relative value units 

for a particular procedure differ based on whether it is furnished in a facility (e.g., HOPD or 

ASC) or a physician office. 

ORGANIZATION OF THIS REPORT 

This report is divided into seven sections. Section 2 provides a summary of the expert 

panel process. Section 3 follows with a description of our empirical evaluation of Medicare 

administrative data for beneficiaries receiving one of the study procedures in 2001. The results 

from both the expert panels and the empirical analyses are then summarized by study procedure 

in the following sections: Section 4, MRI of the Head, Neck, and Brain; Section 5, Cataract 

Surgery; and, Section 6, Colonoscopy. Section 7 discusses the overall findings and conclusions 

from the study. The sections are followed by appendices containing information on the procedures 

included in the data analyses and summaries of the expert panel ratings on the measures that 

were considered by the panelists. 
7 

2. EXPERT PANEL PROCESS 

In this section, we describe the expert panels that were held to rate the study procedures 

(colonoscopy, cataract surgery, and MRI of the head, neck, and brain). We conducted a separate 

expert panel for each study procedure. Panelists were asked to rate the study procedure on three 

dimensions: the preventability and severity of selected outcomes, patient characteristics that might 

affect where care is delivered, and procedure characteristics that might affect the appropriateness 

of furnishing the services in particular settings to patients at different risk levels. We begin with an 

overview of the expert panel process and the rating forms and follow with a discussion of the 

rating process. The results for each expert panel are discussed in subsequent sections of this 

report. More detailed descriptions of the panel process, including a summary of the results for all 

indicators rated by each panel, are found in the appendices. The relevant sections and 

appendices are: 

Procedure Section Appendix

MRI of the Head, Neck, and Brain 4 B 

Cataract 5 C 

Colonoscopy 6 D 

OVERVIEW OF THE EXPERT PANEL PROCESS 

We used a modified version of the RAND appropriateness method for the expert panel 

process (Fitch et al., 2001). Generally, the method quantitatively assesses the expert judgments 

of a group of clinicians by using a scale of values ranging from 1 to 9 and a measure of 

dispersion. We identified a panel of experts for each procedure by contacting individuals from a 

list of nominations we received from national medical societies and organizations (see Table 2.1). 

We formed a separate nine-member panel for each study procedure. In doing so, we sought a 

balanced representation of individuals from the different specialties involved in the care of patients 

receiving the procedure who were practicing in both academic and non-academic settings in 

different geographic regions. The appendix for each study procedure includes a list of the expert 

panel members for that procedure. 
8 

Table 2.1 List of Organizations Contacted for Expert Panel 

Name Provided Nominations 

The American Gastroenterological Association Yes 

American College of Gastroenterology Yes 

American Society for Gastrointestinal Endoscopy Yes 

American Gastrointestinal Endoscopic Surgeons No 

American Society of Colon and Rectal Surgeons Yes 

American College of Physicians Yes 

American Medical Association No—referred to ACP, SGIM 

Society of General Internal Medicine Yes 

Society of Gastroenterology Nurses and Associates Yes 

American Academy of Family Physicians Yes 

American Society of Neuroradiology Yes 

American Academy of Neurology Yes 

American Academy of Ophthalmology Yes 

American Ophthalmological Society No—referred to AAO 

American Society of Cataract and Refractive Surgery Yes 

American Society of Anesthesiology Yes, but RAND staff were unable to confirm participants 

from the list; alternate candidates from opinion leaders 

agreed to participate. 

Each panelist was sent the literature review applicable for the study procedure along with 

an initial rating form. Following feedback on the initial ratings, we held a teleconference meeting 

under the leadership of a facilitator experienced in using the appropriateness method. Although 

each panel had nine identified participants who returned initial rating forms, the cataract and MRI 

panels each had one member who did not participate in the telephone meeting. During the 

meeting, panelists discussed the ratings, focusing on areas of disagreement, and were given the 

opportunity to modify the rating forms. After the discussion, panelists provided final ratings. 

Panelists were requested to rate all items, but some did not do so. As discussed in greater detail 

below and in the appendices, the outcome indicators were rated twice while patient characteristic 

and appropriateness indicators were rated once and there were slight variations in the process 

used for each panel. We did not force the panels to achieve consensus. 

In addition, panelists were encouraged to briefly synthesize issues apart from the narrower 

discussion of the ratings. These discussions ranged from whether the findings are generalizable to 

other procedures and whether certain patient sub-groups might require more resources to any 

concerns the panelists might have with legal and regulatory issues and payment policies. RAND 

staff took notes on these discussions and relevant portions are presented in this report in Section 

7. 
9 

PREVENTABILITY AND SEVERITY OF OUTCOMES 

In general, the literature that we reviewed identified complications, rather than outcomes 

measuring the effectiveness or positive impact of the procedure on patient’s health. Drawing on 

our literature review, we developed a listing of adverse outcomes or complications for each 

procedure that are potentially identifiable through administrative data. We did not include 

complications that are identifiable only in the medical record. We sent a rating form with these 

indicators and instructions to the panelists for the first round ratings. For each indicator, the 

panelists rated the preventability and severity of the outcome on a scale of 1 to 9. The definitions 

and scale from the rating form instructions are summarized in Table 2.2. The panelists rated each 

indicator twice in a two-round “modified Delphi” process. In the first round, the panelists rated the 

indicators before the meeting, with no interaction among panelists. We compiled the ratings and 

sent to each panelist an individualized document showing the distribution of all the experts’ first 

round ratings, together with his or her own specific ratings. 

Table 2.2 Definition and Scale Used to Rate Preventability and Severity

Dimension Definition Scale 

Preventability Likelihood that an outcome can be avoided if the 

individuals or system involved in delivering care follow 

standard practices. (Adapted from Hofer and Haywood, 

2002). 

1 = Not preventable 

5 = Somewhat 

 preventable 

9 = Definitely 

 preventable 

Severity The potential effect of the outcome of the procedure on 

the patient’s life expectancy and quality of life. 

1 = Not severe 

5 = Somewhat severe 

9 = Very severe 

Table 2.3 illustrates the summary rating for an outcome (capsule rupture or posterior 

capsule tear) during cataract removal that was sent to a member of the cataract panel following 

compilation of the initial ratings. The 1 to 9 rating scale for the outcome is shown in bold. In 

parentheses beside the scale, the median and the mean absolute deviation from the median are 

provided. For preventability, the median was 6.0 and the mean absolute deviation from the 

median was 1.3. The distribution of the ratings by the panelists is shown above the scale in italics, 

e.g., one panelist gave a preventability rating of “3” while two panelists rated the complication as 

“8” on the preventability scale. The ^ indicates the initial rating given by the panelist receiving the 
10 

summary. This particular panelist gave the outcome a “3” rating for preventability and a “2” rating 

for severity. 

Table 2.3 Example of Line Item from Initial Round Rating Summary for Outcome Section of the Cataract Panel 

Rating Form 

Outcome Preventability Severity 

 1 1 2 2 1 2 3 2 1 2 1 

1 2 3 4 5 6 7 8 9 (6.0, 1.3) 1 2 3 4 5 6 7 8 9 (3.0, 1.2) Capsule rupture or posterior capsule 

tear 

 ^ ^ 

At the teleconference meeting, the panelists were provided an opportunity to modify the 

rating form and, after discussion, to re-rate the outcomes. Some panelists did not rate all 

measures. In compiling the final ratings, indicators with median scores in the 1-3 range are 

classified as low severity or low preventability, those in the 4-6 range as uncertain, and those in 

the 7-9 range as severe or preventable. The results were defined as uncertain if the ratings were 

dispersed across all three segments of the rating scale. No agreement was defined as at least two 

panelists rating the indicator as low severity (or low preventability) and at least two panelists rating 

the indicator as severe (or preventable). The results for each panel are discussed separately in 

Sections 4-6. 

PATIENT CHARACTERISTICS 

One objective of our study was to identify outcomes that vary by outpatient settings and to 

determine if procedure and patient characteristics vary by the outpatient settings in which the 

service is provided. For most RAND appropriateness panels, the indicators are derived from the 

literature review. Because the literature review did not identify patient characteristics that vary by 

outpatient settings of care, we developed a set of possible indicators related to patient 

characteristics that could be identified through administrative data. In the initial mailing, panelists 

were asked to submit a short list of patient characteristics that might affect selection of site of care 

of the procedure. Based on panelists' suggestions, clinician input from the RAND study team, and 

medical consultant suggestions, we developed a list of quality indicators related to patient 

characteristics. We distributed the second section of the final rating form with these indicators to 

the panelists in advance of the teleconference discussion. During the teleconference, the 

panelists reviewed the indicators and provided ratings on the risk of performing the procedure in 
11 

each setting for each patient characteristic. Using the 1 to 9 scale, low risk was defined as “1” and 

high risk was defined as “9.” Since none of the study procedures are high-risk procedures, the 

panelists were asked to rate relative risk. Panelists rated the patient characteristic indicators once 

only. 

Below is an example of the rating for patients older than age 70 from the cataract panel. 

The rating scale is shown in bold and the numbers in italics show the distribution of the panelist 

ratings. In compiling the ratings, indicators with median scores in the 1-3 range were classified as 

no risk, those in the 4-6 range as uncertain, and those in the 7-9 range as relatively higher risk. 

The results were uncertain if the individual ratings were dispersed across the rating scale. No 

agreement was defined as at least two panelists rating the indicator as no risk and at least two 

panelists rating the indicator as relatively higher risk. The results for each panel are discussed 

separately in the sections that follow the overview. 

Table 2.4 Example of Line Item for Patient Characteristic Section of Cataract Rating Form

Cataract performed for a patient with the 

following characteristic (based on 

information derived from administrative 

or claims data, not medical records): 

Procedure performed in a HOSPITAL 

OUTPATIENT DEPARTMENT 

1=Low risk7

9=High risk 

Procedure performed in an 

AMBULATORY SURGICAL CENTER 

1=Low risk 

9=High risk 

Age > 70 years 

3 4 

1 2 3 4 5 6 7 8 9 

3 3 

1 2 3 4 5 6 7 8 9 

PROCEDURE CHARACTERISTICS 

 Another objective of the study was to determine if procedure characteristics vary by the 

ambulatory settings in which the service is provided. To address this question, the third section of 

the final rating form was used to rate the appropriateness of performing procedures with certain 

characteristics in each setting of care on patients at different risk levels. Because the literature 

review did not identify procedure characteristics that vary by outpatient settings of care, we used 

the same process to develop the list of procedure characteristics as we used for patient 

characteristics (see above). Panelists were asked to rate the appropriateness of providing 

particular procedures to patients at three levels of risk (normal or very low risk, low to moderate 

 7 The forms sent to the panelists referenced risk of mortality. However, at each panel meeting, clarifying instructions were 

provided to request that the rating be based on relative risk. 
12 

risk, and moderate risk). We did not use a category for high risk because the study procedures 

are not likely to be performed on a high- risk patient in an ambulatory setting, if at all. The rating 

forms defined appropriate as follows: 

A service is judged to be appropriate only if the benefit of the medical action (to the 

patient) exceeds the risk of the action (to the patient) by a wide enough margin that 

the service is worth doing (Adapted from Brook et al., 1987). 

The rating scale used to define appropriateness was: 

1=Extremely inappropriate 

5=Equivocal (neither clearly appropriate nor clearly inappropriate) 

9=Extremely appropriate 

Table 2.5 is an example of the portion of the cataract rating form for procedure 

characteristics. The example requests appropriateness ratings for performing CPT 66852 on 

patients in the three risk categories in an HOPD. Another portion of the form asked for the 

appropriateness ratings in an ASC for the same risk categories. The rating scale is shown in bold 

and the panelist ratings are italicized. 

We distributed the rating forms with the appropriateness indicators and instructions to the 

panelists in advance of the teleconference discussion. During the teleconference, the panelists 

reviewed the indicators and provided the appropriateness ratings. In compiling the ratings, 

indicators with median scores in the 1-3 range are classified as inappropriate, those in the 4-6 

range as equivocal, and those in the 7-9 range as appropriate. The results were uncertain if the 

ratings were dispersed across all three segments of the rating scale. No agreement was defined 

as at least two panelists rating the indicator as inappropriate and at least two panelists rating the 

indicator as appropriate. The results for each panel are discussed separately in Sections 4-6. We 

used the results from the expert panels to inform our empirical evaluation of administrative data 

for beneficiaries receiving a study procedure in 2001. An overview of these analyses is presented 

in the next section. 
13 

Table 2.5 Illustration of Line Item for Procedure Characteristics Section of Cataract Rating Form 

Cataract surgery performed 

in a HOSPITAL 

OUTPATIENT 

DEPARTMENT for 

a patient undergoing the 

following type of procedure: 

NORMAL OR VERY LOW 

RISK 

1=Extremely inappropriate 

5=Equivocal (neither clearly 

appropriate nor clearly 

inappropriate) 

9=Extremely appropriate 

LOW-MODERATE RISK 

1=Extremely inappropriate 

5=Equivocal (neither clearly 

appropriate nor clearly 

inappropriate) 

9=Extremely appropriate 

MODERATE RISK 

1=Extremely inappropriate 

5=Equivocal (neither clearly 

appropriate nor clearly 

inappropriate) 

9=Extremely appropriate 

Removal of lens material; 

pars plana approach, with or 

without vitrectomy (66852) 

1 1 1 3 

1 2 3 4 5 6 7 8 9 

1 1 1 3

1 2 3 4 5 6 7 8 9 

1 1 1 1 2

1 2 3 4 5 6 7 8 9 

15 

3. EMPIRICAL EVALUATION OF MEASURES 

After the expert panel ratings were compiled, we tested the feasibility of using 

administrative data to measure differences in the indicators among the ambulatory settings. The 

objectives of these analyses were: 

• To evaluate the extent to which the patient population receiving a procedure and/or the 

nature of the procedures within that grouping varied by setting; 

• To assess the feasibility of identifying complications and adverse outcomes that might 

occur during or after a procedure using administrative data; and, 

• To identify variables in the administrative data that differentiate characteristics of the 

service. 

 We focused on outcome and complication rates and on patient and procedure characteristics 

identified by the literature review and clinical expert advice for the three study procedures and 

informed by the expert panel ratings. Below we describe the methods employed to accomplish these 

objectives, including the data sources, construction of the analytic files, the beneficiary sample 

definition, and calculation of the measures. The results for the three study procedures are discussed in 

Sections 4-6. 

DATA SOURCES 

The enrollment and demographic variables for Medicare beneficiaries for these analyses 

were derived from the Center for Medicare and Medicaid Services (CMS) 5% Denominator File. 

SSS assigned HCC risk scores for 2001 using 2000 administrative data.8 The analyses used data 

on inpatient and outpatient utilization from Medicare Part A and Part B claims. The variables 

related to utilization of inpatient and outpatient care by Medicare beneficiaries were extracted from 

 8 The HCC model assigns a risk score based on a beneficiary’s expected service use given their demographic 

characteristics (age, sex, etcetera) and medical conditions relative to that of the national average beneficiary. It can be used 

to identify patients who are likely to have complex medical needs. Such patients may be at higher risk for complications than 

other patients and may require closer monitoring throughout a surgical procedure and recovery. 
16 

claims represented in the 5% Physician/Supplier Standard Analytic File (SAF), the 5% Hospital 

Inpatient SAF, and the 5% Hospital Outpatient SAF. 

FILE CONSTRUCTION 

The analytic files for our study contained enrollment data and claims for care (inpatient and 

outpatient) provided during calendar year 2001 (CY2001) to Medicare beneficiaries who had one 

of three study procedures between January 1 and December 31, 2001. The three procedures, 

which we refer to as index procedures, were: MRI of the head, neck, and brain (BETOS I2C), 

cataract removal/lens insertion (BETOS P4B), and colonoscopy (BETOS P8D). The CPT codes 

included in each procedure grouping are listed in Appendix A. To be included in the sample, 

beneficiaries must have had the procedure performed in one of four ambulatory settings: 

• Hospital outpatient department (HOPD) 

• Ambulatory surgical center (ASC) 

• Physician office (Office) 

• Independent diagnostic testing facility (IDTF) 

Social and Scientific Systems, Inc. (SSS) created extract files containing all records from the 5% 

Denominator file, the 5% Physician/Supplier SAF, the 5% Inpatient SAF, and the 5% Outpatient 

SAF for this sample of beneficiaries. From these files, we created four mutually exclusive files for 

each of the three index procedures. The four files were: 

1. Index Procedure File: A standardized record for each index procedure performed during 

CY2001. Each record in this file represents one index procedure and related services 

received on the same date as the index procedure and includes variables from the 

Denominator File and variables that relate to the index procedure from the various SAFs, 

including diagnoses, provider specialties, and other procedures. 

2. Physician/Supplier Claim File: All physician/supplier claims for care received in any setting 

during CY2001 for beneficiaries with an index procedure performed during CY2001. 

3. Inpatient Claim File: All facility claims for care received in an inpatient hospital during 

CY2001 for beneficiaries with an index procedure performed during CY2001. 
17 

4. Hospital Outpatient Claim File: All facility claims for HOPD care received during CY2001 for 

beneficiaries with an index procedure performed during CY2001. 

The claims in Files 2 through 4 do not include the care (i.e., anesthesia and all other care) 

in the index procedure file. In addition, the care in these files is not necessarily related to the 

index procedure (e.g., MRI). Claims for durable medical equipment, skilled nursing facilities, 

home health agencies, and hospice are not included in these analyses. 

The index procedure file contains a single fixed length record for each index procedure with 

a standardized set of variables, regardless of which ambulatory setting the procedure was 

performed in. A beneficiary can have more than one record in the index procedure file if s/he had 

more than one index procedure (MRI, cataract surgery, or colonoscopy) on different dates in 

2001. The three index files include records for all procedures with the HCPCS (CPT) codes 

included in the BETOS categories for MRI of the head, neck, and brain (BETOS I2C), cataract 

removal/lens insertion (BETOS P4B), and colonoscopy (BETOS P8D) (Appendix A). In addition, 

the cataract file included one code, CPT 66820 9 that is in BETOS P4E (Eye procedure-other) 

based on clinical input. All variables in the index procedure file record were derived from one or 

more claims for the index procedure. 

For index procedures performed in an ASC or IDTF, the record generally contains variables 

from a physician/supplier SAF claim for the facility service and a physician/supplier SAF claim for 

the related physician services. For index procedures performed in the HOPD, the record 

generally contains variables from an outpatient SAF claim (i.e., facility) and physician/supplier 

SAF claim. For index procedures performed in a physician office, the record only contains 

variables from a physician/supplier SAF claim. Claims for anesthesia services furnished in 

conjunction with the index procedure in any of the sites were identified in the physician/supplier 

file and added to the index procedure record. 

Variables in the index procedure files included diagnosis and procedure codes from the 

facility and physician claims, as well as the date of service, modifier codes, and provider specialty 

for each procedure. The 2001 HCC Risk Score (based on 2000 data) for each beneficiary was 

merged onto the record from a file created by SSS prior to this project. Separate variables for 

 9 Discission of secondary membranous cataract (opacified posterior lens capsule and/or anterior hyaloid); stab 

incision technique (Ziegler or Wheeler knife).
18 

diagnosis and procedure codes, modifier codes and provider specialty were created for 

anesthesia-related services. In addition, the time unit counts and base unit count were included 

for each anesthesia code. 

STATISTICAL ANALYSIS 

We restricted the sample to beneficiaries who were enrolled in both Part A and Part B of 

Medicare and were in traditional fee-for-service Medicare for at least one month during CY2001. 

We excluded beneficiaries who were enrolled in a Medicare managed care organization because 

utilization data for their inpatient and outpatient care are not available. In calculating each 

measure, we included all beneficiaries who were enrolled in Medicare fee-for-service for at least 

one month (the period used in these preliminary analyses to measure adverse outcomes). 

MRI (head, neck, and brain) is performed in three ambulatory settings: HOPDs, physician 

offices, and IDTFs. Cataract removal/lens insertion and colonoscopy are performed in a different 

three ambulatory settings: HOPDs, ASCs, and physician offices. Using the files described above, 

we compared numerous characteristics of the beneficiaries and procedures among the 

ambulatory settings. These included demographic characteristics, the type of procedure, the 

average HCC risk score, other procedures performed on the same date or included on the same 

facility or physician claim as the index procedure, diagnoses coded on the facility and physician 

claims for the index procedure, and provider specialty. For the type of procedure, we first 

classified MRIs by HCPCS code and then collapsed them into two categories: those with contrast 

and those without contrast.10 We also categorized the HCPCS codes for colonoscopies into two 

categories: those with some lesion removal, biopsy, or control of bleeding (RBC) and those 

without RBC.11 We used these collapsed procedure categories for MRI and colonoscopy in 

calculating the average risk scores. In addition, for each index procedure, we tabulated the 

number of procedure codes within the same BETOS that reported as being performed on the 

same day to learn if they were being performed multiple times. 

We also calculated the percentage of beneficiaries who exhibited characteristics that might 

increase their risk of an adverse outcome following the procedure (i.e., risk factors) or 

 10 The HCPCS codes for MRI with contrast are 70541, 70542, 70543, 70545, 70546, 70548, 70549, 70552, and 

70553. The HCPCS codes for MRI without contrast are 70544, 70547, and 70551.

11 The HCPCS codes for RBC colonoscopy are 44389, 44391, 44392, 44393, 44394, 45379, 45380, 45382, 45383, 

45384, 45385, and 45387. The HCPCS codes for “non-RBC” colonoscopy are 44388, 45378, and G0105.
19 

characteristics that indicate they should not have the procedure (i.e., contraindications). We 

developed a list of possible risk factors and contraindications, referred to hereafter as “patient 

characteristics,” based on clinician input from the RAND team, medical consultant suggestions 

and the panelists' suggestions. 

After the panel meeting, we selected a subset of the patient characteristics for the claims 

analysis on the basis of the rating results. The panel rated the risk level for patients with the 

specified characteristic for each of the three ambulatory settings separately. The panel rated each 

characteristic on a 1-to-9 scale, with 1 being low risk and 9 being high risk. We selected for 

analysis characteristics with a median risk rating of 4 or higher in any of the three ambulatory 

settings. Based on this criterion, we selected 8 patient characteristics to be analyzed for MRI 

(head, neck, and brain), 17 for cataract surgery, and 12 for colonoscopy.12 

We constructed algorithms to define these measures, specifying the patient characteristic 

in terms of diagnosis or procedure codes (ICD-9-CM, CPT, and HCPCS), and the time frame 

preceding the procedure (a time period specified in the patient characteristic wording or, if no time 

period is specified in the wording of the patient characteristic, from January 1, 2001 until the day 

preceding the procedure). We searched claims for all settings of care (inpatient, outpatient, ASC, 

IDTF, and office) to identify each patient characteristic. We calculated the rate for each patient 

characteristic as a percentage based on the number of procedures with a particular characteristic 

divided by the number of procedures. The rates were estimated for each setting separately and 

for all settings combined. We calculated the percentage of beneficiaries who developed an 

adverse outcome or complication within a specified period after each procedure. We developed a 

list of outcomes/complications that might occur following each procedure based on the results of 

the literature review, panelists’ comments prior to the meeting, and the discussion at the expert 

panel meeting. We tested 16 outcome measures for MRI (head, neck, and brain), 24 for cataract 

removal/lens insertion, and 18 for colonoscopy.13 We constructed algorithms to describe the 

 12 One characteristic for colonoscopy that would have been selected based on the panel ratings was not tested in 

the claims analysis because we were unable to identify diagnosis codes for the algorithm.

13 Several outcomes (3 for MRI, 3 for cataract surgery, and 1 for colonoscopy) that were rated by the panels were not 

tested in the claims analysis because we were unable to identify diagnosis codes for the algorithms. For MRI, the outcomes 

were ocular injury, vasospasm, and vasodilation. The colonoscopy condition was post-polypectomy syndrome and the 

cataract surgery outcomes were capsule rupture, wound dehiscence, and wound leak. We have not reported congestive 

heart failure as an outcome because the technical issues related to identifying "new or worsening" congestive heart failure 

were beyond the scope of our study. 
20 

measure, specifying the adverse outcome or complication in terms of diagnosis or procedure 

codes (ICD-9-CM, CPT, and HCPCS), and the time frame following the procedure within which 

the outcome occurred (30 days). We looked for the adverse outcome or complication on claims 

for all settings of care (inpatient, outpatient, ASC, IDTF, and office). We calculated the outcome 

rates as the number of procedures with a particular adverse outcome within the specified time 

period divided by the number of procedures expressed as a percentage. These rates were 

estimated for each setting separately and for all settings combined. For these preliminary 

analyses, we used the same outcome period for all complications and did not try to distinguish 

between complications and co-morbid conditions that might have been present when the 

procedure was performed. The results of our analyses are discussed by type of procedure in the 

next three sections. 

 
21 

4. MRI OF HEAD, NECK, AND BRAIN 

This section summarizes the results from the expert panel and our empirical 

evaluation of administrative data for Medicare fee-for-service beneficiaries who received 

an MRI of the head, neck, or brain. These procedures are assigned to BETOS 12C (see 

Appendix A for a listing of the specific procedures) and account for slightly more than 

0.5 percent of Medicare’s volume and 2.3 percent of its payments for diagnostic and 

therapeutic procedures in ambulatory settings (exclusive of evaluation and management 

services, professional anesthesia services, outpatient rehabilitation therapy services 

and laboratory tests).14 MRI of the head, neck and brain was selected as a study 

procedure because it is a high cost diagnostic procedure that is performed in IDTFs as 

well as HOPDs and office settings. 

Our review of the literature found that in general, MR imaging is associated with 

relatively few safety concerns. MR imaging is contraindicated for some patients with 

metallic foreign bodies or implants. Most patients without contraindications who undergo 

non-contrast cranial MR imaging tolerate the procedure without experiencing adverse 

events. Patients without contraindications who undergo contrast-enhanced MRI also 

have few adverse reactions. When patients do experience complications, the 

complications can be grouped into the following categories: clinical symptoms and 

signs, changes in vital signs, changes in other parts of the physical exam, and changes 

in laboratory values. It was not clear in our review of the literature whether the 

complications could be attributed to the MR procedure or contrast in part because the 

studies included in this review did not have control groups receiving no MR imaging 

and/or contrast. 

EXPERT PANEL RESULTS 

 The results of the expert panel rankings for all measures are shown in Appendix 

B. In this section, we summarize the results and highlight those that suggest there may 

 14 This calculation does not include DME, drugs and medical supplies, and outpatient dialysis and 

accounts only for professional and facility services provided in physician offices, ASCs, HOPDs, and IDTFs. 
22 

be differences across the settings in patient characteristics, procedure characteristics, 

or outcomes. 

Patient Characteristics 

The expert panel was asked to rate the relative risk of performing an MRI on 

patients with particular characteristics or conditions in three settings: HOPD, IDTF, and 

physician office. Reflecting the generally low-risk nature of the MRI, the risk of 

performing the procedure in any of the settings was most often rated low. The ratings 

were similar across the settings, with HOPDs rated as having slightly less risk for many 

procedures. In general, ratings for IDTFs and physician offices were the same. The 

panel discussion reflected concern that the structural differences, if any, are not clearly 

defined between IDTF and physician office settings, particularly with respect to the level 

and type of physician involvement. 

Only one condition- myocardial infarction within past 7 days - was rated as 

posing moderate risk across all three settings. The median ratings for unstable angina 

in last 3 months and for recent myocardial infarction (more than 7 days and less than 30 

days ago) were at the high end of relatively low risk in HOPDs and at the low end of 

moderate risk in the community settings. Patients with an automatic implanted 

cardioverter defibrillator (AICD) implant, for which MRI is contraindicated, uniformly 

received the highest risk ranking. There was no agreement on the relative risk posed by 

foreign bodies in the eye. 

Procedure Characteristics 

The MRI panel was asked to rate the appropriateness of performing an MRI with 

and without contrast dye, with anesthesia, or with high dose contrast media in the 

different settings. In these ratings, a separate category for emergency room (nonscheduled) MRIs was included in addition to the HOPD. There was agreement that 

performing an MRI with or without dye in any of the settings was appropriate for patients 

that are from normal to moderate risk. There was also agreement that performing an 

MRI with anesthesia was appropriate in a hospital setting but there was no agreement 
23 

regarding whether it was appropriate in the community settings. Similarly, the panelists 

did not agree or had inconclusive ratings for high dose contrast MRI. 

Outcomes 

The MRI panel was asked to rate 18 potential outcomes associated with an MRI 

on two dimensions: preventability and severity. The panelists rated no complications as 

both highly preventable and very severe. Ocular injury was the only complication that 

the panelists agreed were preventable; there was not agreement on whether death 

would be preventable. All other complications received low preventability ratings. 

There were two complications that the panelists agreed were severe: death and 

anaphylaxis/anaphylactoid. Panelist ratings were inconclusive regarding the severity of 

four complications: dyspnea (shortness of breath), ocular injury, seizure and syncopy. 

Other complications were rated as not severe. 

In discussion, the panel indicated that these measures would be generalizable to 

other MRI and magnetic resonance angiography (MRA) procedures, with and without 

contrast media. 

EMPIRICAL EVALUATION RESULTS 

The results of the claims analyses for MRI of the head, neck, and brain (hereafter 

referred to as MRI) are shown in Tables 4.1 through 4.8 based on a 5 percent sample of 

Medicare beneficiaries in CY2001. In this sample, a total of 40,497 MRIs were 

performed on Medicare beneficiaries during CY2001 (Table 4.1). Of MRIs performed in 

an ambulatory setting, about half are performed in an HOPD (52 percent) and the 

remaining MRIs are done in the office (36 percent) or an independent diagnostic testing 

facility (11 percent). A smaller percentage of beneficiaries who are under the age of 65, 

originally disabled or Medicaid eligible have MRIs performed in the office setting than in 

an HOPD or IDTF. A higher percentage of MRIs in the HOPD are for African-American 

beneficiaries than in the office or IDTF. 

Seven of the nine geographic regions showed a similar pattern of MRIs by 

ambulatory setting with the largest percentage performed in an HOPD (43 to 71 

percent), followed by office (24 to 37 percent), and IDTF (7 to 20 percent) (Table 4.2). 
24 

Two geographic regions exhibit a different distribution of MRIs by ambulatory setting. In 

New England, a much higher percentage of MRIs are performed in an IDTF (28 

percent) than in other regions. In the Middle Atlantic, a smaller percentage of MRIs are 

performed in the HOPD (31 percent) with a higher percentage in the office (64 percent). 

Procedure Characteristics 

In the three ambulatory settings combined, almost 58 percent of MRIs were 

performed with the use of contrast media while in the remaining 42 percent; contrast 

was not used (Table 4.3). A higher percentage of MRIs were performed with contrast 

media in the HOPD than in the other two ambulatory sites. More than 62 percent of 

claims for MRI in the HOPD included at least one HCPCS code indicating an MRI was 

performed with contrast, compared to 53 percent of MRI claims in the office and in the 

IDTF. 

In the three settings combined, almost 20 percent of the MRI claims in this 2001 

sample had more than one MRI procedure within BETOS I2C coded (Table 4.3). This 

pattern of care differed among settings, however, from 12 percent of the HOPD claims 

having more than one MRI coded to 28 percent of office claims with multiple MRI codes. 

While there are modifier codes to distinguish between multiple procedures that are 

performed in the same session and distinct procedures that are performed on the same 

day during different sessions, they were reported on only a handful of claims and could 

not be used to determine whether the procedures were done at the same or different 

times on the same day.15

 15 Generally, only modifier codes needed for particular Medicare payment provisions (e.g., professional 

component only, location in an urban health professional shortage area) were reported and the modifiers did 

not add information regarding the nature of the procedure. 
25 

Table 4.1 Characteristics of Beneficiaries with MRI of Head, Neck, Brain (BETOW 12C) By Ambulatory Setting, Medicare Fee

Characteristic

N %* N %* N %* N 

Total 21,233 100.00 14,712 100 4,552 100 40,4Male 8,340 39.3 5,669 38.5 1,677 36.8 15,6Female 12,891 60.7 9,043 61.5 2,875 63.2 24,8Age in years at time of procedure

Under 65 3,183 15.0 1,697 11.5 641 14.1 5,5265-69 3,771 17.8 2,622 17.8 830 18.2 7,2270-74 4,774 22.5 3,405 23.1 1,004 22.1 9,1875-79 4,691 22.1 3,441 23.4 981 21.6 9,1180-84 3,069 14.5 2,380 16.2 737 16.2 6,1885 and Over 1,745 8.2 1,167 7.9 359 7.9 3,27

White 19,009 89.5 13,304 90.4 4,116 90.4 36,4African-American 1,510 7.1 826 5.6 211 4.6 2,54Other 714 3.4 582 4.0 225 4.9 1,52Originally disabled 4,599 21.7 2,582 17.6 951 20.9 8,13Medicaid eligible for 1 or more months 3,450 16.2 1,770 12.0 795 17.5 6,01End-stage renal disease 167 0.8 88 0.6 37 0.8 292 *Numbers in this column represent percentages of column total.Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

HOPD Office IDTF A
26 

Table 4.2 Percentage of MRI of Head, Neck, and Brain (BETOS 12C) Preformed In Three Ambulatory Settings, Medicare Fee-

Census Region***

N %* N %* N %* 

Total 21,233 52.4 14,712 36.3 4,552 11.2 

New England 979 50.6 414 21.4 543 28.0 Middle Atlantic 1,941 30.6 4,084 64.4 317 5.0 East North Central 4,063 66.4 1,662 27.2 394 6.4 West North Central 1,888 66.2 686 24.1 276 9.7 South Atlantic 4,567 49.9 3,527 38.5 1,065 11.6 East South Central 2,109 71.0 589 19.8 273 9.2 West South Central 2,712 61.7 1,108 25.2 573 13.0 Mountain 1,084 50.6 790 36.9 269 12.6 Pacific 1,802 43.3 1,526 36.7 835 20.1 *Numbers in this column represent percentages of row total.**Numbers in this column represent percentages of column total.***New England: Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, Vermont

Middle Atlantic: New Jersey, New York, PennsylvaniaEast North Central: Illinois, Indiana, Michigan, Ohio, WisconsinWest North Central: Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, South DakotaEast South Central: Alabama, Kentucky, Mississippi, TennesseeWest South Central: Arkansas, Louisiana, Oklahoma, TexasMountain: Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, WyomingPacific: Alaska, California, Hawaii, Oregon, Washington

Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

South Atlantic: Delaware, District of Columbia, Florida, Georgia, Maryland, North Carolina, South Carolina, Virginia

HOPD Office IDTF 
27 

Table 4.3 Distribution of MRI Head, Neck, and Brain (BETOS 12C) by HCPCS and Number of Procedures Coded for Same Da

Medicare Fee-for-Service System, 2001

HCPCS HCPCS Description

N %* N %* N 

All MRI, Brain 21,233 100 14,712 100 4,552 

Contrast MRI** 13,199 62.2 7,742 52.6 2,410 Non-contrast MRI*** 8,034 37.8 6,970 47.4 2,142 

One procedure 18649 87.8 10582 72.0 3473 

70541 Magnetic resonance angiography, head and/or neck, with or without 

contrast material(s). 226 1.1 41 0.3 9 

70542 MR (eg, proton) imaging, orbit, face, and neck; with contrast material 40 0.2 10 0.1 1 70543 MR (eg, proton) imaging, orbit, face, and neck; without contrast 

material, followed by contrast material(s) and further sequences. 232 1.1 201 1.4 66 

70544 MR angiography, head; without contrast material(s) 337 1.6 211 1.4 72 70545 MR angiography, head; with contrast material(s) 37 0.2 3 0.0 1 70546 MR angiography, head; without contrast material, followed by

contrast material(s) and further sequences. 65 0.3 13 0.1 6 

70547 MR angiography, neck; without contrast material(s) 338 1.6 338 2.3 66 70548 MR angiography, neck; with contrast material(s) 119 0.6 34 0.2 14 70549 MR angiography, neck; without contrast material, followed by

contrast material(s) and further sequences. 266 1.3 141 1.0 29 

70551 Magnetic resonance (eg, proton) imaging, brain (including brain 

stem); without contrast material 5,508 25.9 3,877 26.4 1,305 

70552 Magnetic resonance (eg, proton) imaging, brain (including brain 

stem); with contrast material(s). 556 2.6 175 1.2 25 

70553 Magnetic resonance (eg, proton) imaging, brain (including brain 

stem); without contrast material, followed by contrast material(s) and further sequences.

10,925 51.5 5,538 37.7 1,879 

Two procedures 2,009 9.5 2,834 19.3 699 Three procedures 570 2.7 850 5.8 285 Four procedures 5 0.0 269 1.8 57 Five procedures 0 0.0 172 1.2 38 *Numbers in this column represent percentages of column total.***Non-contrast MRI includes the following HCPCS codes: 70544, 70547, and 70551.**Contrast MRI includes the following HCPCS codes: 70541, 70542, 70543, 70545, 70546, 70548, 70549, 70552, and 70553.Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

HOPD Office I
28 

In all three settings, the most common codes on records with one procedure 

were coded as MRI without contrast (CPT 70551), or MRI without contrast followed by 

with contrast (CPT 70553) (Table 4.3). Among those records with two MRIs coded, the 

two most commonly performed combinations were (1) MRA without contrast (CPT 

70544) and MRI without contrast (CPT 70551), and (2) MRA without contrast (CPT 

70544) and MRI without contrast followed by with contrast (CPT 70553). 

Radiologists (diagnostic or interventional) perform a high percentage of MRIs in 

the HOPD (80 percent), and office (88 percent) (Table 4.4).16 The expert panelists 

asked what specialties are involved when the MRI is performed in an IDTF. We found 

that about 65% of MRIs are billed as a global procedure with the IDTF specialty code so 

that the specialty of the physician supervising the procedure cannot be determined. 

Separate technical and professional components are billed for about 35% of the 

procedures. The table reflects the lower incidence of separate claims for professional 

services in IDTFs. If the specialty distribution in IDTFs were determined solely on the 

professional claims, radiologists were involved in 84 percent of the procedures. In the 

IDTF and office settings, a neurologist does most of the remaining MRI procedures. In 

the HOPD, most of the rest are coded as “multispecialty clinic or group practice.” 

Overall, residents were reported as performing the procedure under the supervision of a 

teaching physician on 5 percent of the professional claims for HOPD procedures 

compared to 0.5 percent and 0.2 percent of claims for procedures performed in 

physician offices and IDTFs, respectively (data not shown). 

 16 The percentage for MRIs performed by a radiologist in the IDTF is much lower because, of the 4,552 MRIs 

performed in the IDTF, only 1,344 have a professional line item with the index HCPCS. 
29 

Table 4.4 Top five Specialties* of Providers Performing MRI of Head, Neck, and Brain (BETOS 12C) 

By Ambulatory Setting, Medicare Fee-for-Service System, 2001

Setting Specialty Code Specialty Description Number Percent**

HOPD 30 Diagnostic radiology 16,387 77.2

70 Multispecialty clinic or group practice 893 4.2

94 Interventional radiology 501 2.4

13 Neurology 190 0.9

92 Radiation oncology 72 0.3

Office 30 Diagnostic radiology 12,762 86.7

13 Neurology 703 4.8

70 Multispecialty clinic or group practice 357 2.4

94 Interventional radiology 245 1.7

8 Family Practice 119 0.8

IDTF*** 30 Diagnostic radiology 1,129 24.8

13 Neurology 108 2.4

70 Multispecialty clinic or group practice 68 1.5

94 Interventional radiology 27 0.6

92 Radiation oncology 6 0.1

The percentages do not total 100 percent because they represent only the top five specialties.

**Numbers in this column represent percentages of all procedures performed in the indicated setting. 

Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

*Specialties were derived from the claims for professional services associated with the procedure.

***About 65 percent of the IDTF records were global bills with no specialist indicated.
30 

Patient Characteristics 

We used the risk scores assigned to each beneficiary by the hierarchical 

condition category (HCC) risk adjustment model to determine if more medically complex 

patients are treated in a particular setting. In each of the sites separately and the three 

sites combined, the average HCC risk score is higher for patients undergoing MRI with 

contrast than for MRI without contrast (Table 4.5). For contrast MRIs, the risk scores 

are highest among HOPD patients followed by office and IDTF patients. For noncontrast MRIs, the pattern is reversed with the risk scores of HOPD patients the lowest, 

followed by IDTF and office patients. 

Table 4.5 Average Risk Scores for Beneficiaries With MRI of Head, Neck, and Brain (BETOS 12C) By 

Ambulatory Setting, Medicare Fee-for-Service System, 2001 

HCPCS Procedure Category HOPD Office IDTF All Sites

All MRI, Brain 1.27 1.25 1.23 1.26

Contrast MRI* 1.31 1.26 1.24 1.28

Non-contrast MRI** 1.21 1.24 1.23 1.23

*Contrast MRI includes the following HCPCS codes: 70541, 70542, 70543, 70545,

70546, 70548, 70549, 70552, and 70553.

**Non-contrast MRI includes the following HCPCS codes: 70544, 70547, and 70551.

Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

 

In all three ambulatory settings, the two ICD-9-CM diagnoses coded most frequently 

on the facility claims for MRIs are dizziness and giddiness (ICD-9-CM 780.4) and headache

(ICD-9-CM 784.0)17 (Table 4.6). The percentage of claims with each of the other eight 

diagnoses in the top ten varies somewhat among the three settings. A higher percentage of 

diagnosis codes for MRIs performed in the office and IDTF are related to cerebrovascular 

disease18 than in the HOPD (34 percent for office, 31 percent for IDTF, and 23 percent for 

HOPD). 

17 The diagnoses for the office setting are derived from the professional, rather than the facility, claim.

18 Cerebrovascular-related diagnoses include the following ICD-9-CM codes: 433.10, 435.9, 436, 

331.9, and 437.1.
31 

The prevalence rates of eight characteristics that might increase the risk of an 

adverse outcome (i.e., risk factors) among patients having an MRI are shown in Table 

4.7.19 Each characteristic was identified using all claims for care received by the patient 

in any inpatient or outpatient setting during the months and days of 2001 preceding the 

date of the MRI. The prevalence rates of four risk factors are higher among patients 

having the MRI in the office than in the HOPD or IDTF: unstable angina, myocardial 

infarction in past week, intraocular magnetic foreign body, and foreign body after 

penetrating wound. The prevalence of cerebral edema was higher in HOPD patients 

than in office or IDTF patients. 

Outcomes 

Both general medical outcomes and procedure-specific outcomes occurred at a 

low rate in all three ambulatory settings following MRI (Table 4.8). For all MRIs (with 

and without contrast), the rates for most outcomes were highest in the office setting. 

HOPD rates were slightly lower than rates in the office. Both office and HOPD rates 

were considerably higher than IDTF rates. The overall rates for two outcomes (altered 

mental status and tachycardia) were highest among HOPD patients. After restricting to 

contrast MRI only, however, the rate of altered mental status was lower among the 

HOPD patients than among office patients (data not shown). In addition, the overall 

rate of anaphylaxis/anaphylactoid reaction was highest among IDTF patients; however, 

when restricted to MRI with contrast, the rates for this outcome are similar among the 

HOPD and IDTF patients (data not shown). 

 19 As mentioned in the Methods section, the MRI panel rated these characteristics with a median of 4 or 

higher on a 1-to-9 risk scale, with 9 being high risk.
32 

Table 4.6 Top Ten Diagnoses on Facility Claim* for MRI of Head, Neck, and Brain (BETOS 12C) By Ambulatory Setting, Medi

ICD-9 Code ICD-9 Code Description

N %** N %** N 

780.4 Dizziness and giddiness 2,978 14.0 1,862 12.7 671 

784 Headache 2,595 12.2 1,915 13.0 578 

433.1 Carotid artery occlusion w/o mention of cerebral infarction 1,134 5.3 1,319 9.0 268 435.9 Unspecified transient cerebral ischemia 1,164 5.5 1,156 7.9 293 

436 Acute, but ill-defined, cerebrovascular disease 995 4.7 863 5.9 318 

331.9 Cerebral degeneration, unspecified 965 4.5 823 5.6 291 780.9 General symptoms nec 1,081 5.1 563 3.8 195 437.1 Other generalized ischemic cerebrovascular disease 549 2.6 790 5.4 243 781.2 Abnormality of gait 641 3.0 438 3.0 95 780.2 Syncope and collapse 656 3.1 394 2.7 121 

*Diagnoses for physician office procedures were derived from professional claims.Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.**Numbers in this column represent percentages of all procedures performed in the indicated setting. The percentages do not 

HOPD Office IDT

total 100 percent because they represent only the top ten diagnoses. Multiple diagnoses can be coded on a single claim.
33 

Table 4.7 Selected Risk Factors of Beneficiaries With MRI of Head, Neck, and Brain (BETOS 12C) By Ambulatory Setting, MeSystem, 2001 

Indicator* Risk Factor

N Rate** N Rate** N RATE

BF Retained (old) intraocular foreign body, magnetic 158 7.4 210 14.3 28 6.2 

D Unstable angina in last 3 months 142 6.7 130 8.8 19 4.2 

BC Cerebral edema 45 2.1 7 0.5 3 0.7 

E Myocardial infarction within past 7 days 6 0.3 11 0.7 0 0.0 

BH Retained (old) foreign body following penetrating 

wound of orbit (retrobulbar foreign body) 3 0.1 4 0.3 1 0.2 

AD Patient with Automatic Implanted Cardioverter

Defibrillator (AICD) 1 0.0 2 0.1 0 0.0 

BN Penetrating wound of orbit with foreign body 

(open wound of ocular adnexa) 0 0.0 0 0.0 2 0.4 

BK Penetration of eyeball with magnetic foreign body 

(not old) (open wound of eyeball) 0 0.0 1 0.1 0 0.0 

*Letter codes in this column are taken from the rating form for the RAND expert panel. (Reference Appendix B)**Per 1,000 procedures.Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

HOPD Office IDTF 
34 

Table 4.8 Selected Adverse outcomes Occurring Within 30 Days Following MRI of Head, Neck, and Brain (BETOS 12C) By A

Fee-for-Service System, 2001 

Outcome

N Rate** N Rate** N Rate** 

Dizziness 732 34.5 1,288 87.5 131 28.8 Headache 541 25.5 875 59.5 96 21.1 Chest pain 610 28.7 462 31.4 61 13.4 Seizure 424 20.0 396 26.9 84 18.5 Syncope 399 18.8 420 28.5 58 12.7 Dyspnea 439 20.7 332 22.6 28 6.2 Paresthesia 235 11.1 251 17.1 35 7.7 Bradycardia 150 7.1 112 7.6 15 3.3 Hypotension 75 3.5 68 4.6 9 2.0 Altered Mental Status 39 1.8 22 1.5 4 0.9 Rash 26 1.2 26 1.8 6 1.3 Tachycardia 30 1.4 19 1.3 4 0.9 Other Complications*** 9 0.4 8 0.5 1 0.2 Anaphylaxis/anaphylactoid reaction 6 0.3 3 0.2 2 0.4 Hypertension 1 0.0 3 0.2 0 0.0 Death within 1 week 0 0.0 1 0.1 1 0.2 *Numbers in this column represent the number of outcomes.**Per 1,000 procedures.*** Other complications are diagnosis codes 998.89 (Other specificied complications of procedures, not elsewhere classified) and 998.9 (Unspecified complication of procedures, not elsewhere classified).Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

HOPD Office IDTF
35 

SUMMARY OF FINDINGS 

The purpose of our analyses was to determine if there are differences in patient 

characteristics, processes of care, or outcomes that can be measured through 

administrative data. On the issue of patient characteristics, the panel ratings and 

discussion indicated that MRIs are low risk procedures that can be safely performed in 

the different ambulatory settings. The two conditions that might pose risk- AMI within the 

past 7 days and AICD implant- were thought to be highly unlikely and this is confirmed 

by the empirical evidence. The empirical data also indicated that patients receiving MRI 

with contrast have higher average HCC risk scores than those receiving MRI without 

contrast. Patients receiving MRI in HOPDs have higher risk scores than patients in 

other ambulatory settings. However, after controlling for use of contrast media, the HCC 

pattern of risk scores across the sites is inconsistent. 

The data indicate that a higher proportion of MRIs with contrast are performed in 

HOPDs than in community settings. Both general medical outcomes and procedurespecific outcomes occurred at a low rate in all three ambulatory settings following MRI, 

but differences across the sites are measurable. IDTFs generally had lower 

complication rates (not risk-adjusted) than HOPDs and physician offices. 

37 

5. CATARACT SURGERY 

Extracapsular cataract extraction and phacoemulsification with or without 

intraocular lens implantation are among the most common surgical procedures 

performed in the United States (National Eye Institute, 2003). Almost all cataract 

surgeries are performed in a HOPD, ASC or physician’s office (Javitt et al. 1994). 

Medicare spends more on cataract surgery than any other ambulatory surgical 

procedure, with the procedure accounting for 0.8 percent of Medicare’s volume and 

10.3 percent of its payments for diagnostic and therapeutic procedures in ambulatory 

settings (exclusive of evaluation and management services, professional anesthesia 

services, outpatient rehabilitation therapy services and laboratory tests).20 Cataract 

surgery was chosen as a study procedure because it is a high-volume surgical 

procedure performed in multiple ambulatory settings. 

Most cataract removal surgeries are uncomplicated and lead to improved visual 

acuity and patient satisfaction. In some cases however, postoperative complications 

arise including retinal detachment, intraocular lens malposition or dislocation, vitreous 

loss, endophthalmitis, aphakic and pseudophakic bullous keratopathy, iris prolapse, 

cystoid macular edema, corneal edema, intraocular pressure, chronic uveitis, or vision 

loss. Other complications may arise from the sedation or anesthesia used during the 

procedure. Complications arising from local (injected) anesthesia include retrobulbar 

hemorrhage, globe perforation, strabismus, respiratory arrest, ptosis, and confusion. 

EXPERT PANEL RESULTS 

The results of the expert panel rankings for all measures are shown in Appendix 

C. In this section, we summarize the results and highlight those that suggested 

differences in patient characteristics, procedure characteristics, or outcomes between 

cataract surgeries performed in HOPDs and ASCs. We did not ask the panelists to rate 

cataract procedures performed in physician offices given the relatively small volume of 

 20 This calculation does not include DME, drugs and medical supplies, and outpatient dialysis and 

accounts only for professional and facility services provided in physician offices, ASCs, HOPDs, and IDTFs. 
38 

procedures performed in this setting and lack of definition regarding how the structural 

features and processes of surgery performed in the office setting compare to ASCs. 

Patient Characteristics 

The expert panel was asked to rate the relative risk of performing a cataract 

surgery on patients with particular characteristics or conditions in HOPDs and ASCs. 

There was agreement among the panelists that malignant hypertension and recent 

myocardial infarction (within 30 days) posed relatively high risk in both settings. Several 

conditions were rated as posing moderate risk: dementia, cardiac dysrhythmias 

(paroxysmal ventricular tachycardia and persistent severe sinus bradycardia), and 

history of shock due to anesthesia in which the correct substance was properly 

administered. Ratings were inconclusive for three conditions: unstable angina in the last 

3 months, cardiomyopathy/heart failure/pulmonary edema, and primary pulmonary 

hypertension. There was agreement that the remaining conditions on the rating form 

posed little or no risk in either setting. 

Procedure Characteristics 

The cataract panel was asked to rate the appropriateness of performing various 

types of cataract surgeries in HOPDs and ASCs on patients at three risk levels: normal 

or very low risk, low-moderate risk, and moderate risk. With few exceptions, procedures 

received high appropriateness ratings when performed in either an HOPD or ASC 

across all patient risk categories. One exception was cataract surgery involving general 

anesthesia, which the panelists indicated during discussion should rarely occur. 

Cataract surgery with general anesthesia had an inconclusive rating for moderate risk 

patients in HOPDs. In ASCs, it was rated as inappropriate for moderate risk patients 

and equivocal for normal or low-risk patients. Removal of lens material; pars plana 

approach, with or without vitrectomy also had different ratings across setting. The rating 

for low-moderate and moderate risk patients in ASCs was inconclusive. During 

discussion, several panelists expressed concern over whether a retinal specialist would 

be available during a vitrectomy performed at an ASC. 
39 

Outcomes 

The cataract panel was asked to rate 27 potential outcomes associated with 

cataract surgery on two dimensions: preventability and severity. At the panel meeting, 

the panelists indicated that the post-surgical period for assessing complications should 

be 30 days for eye-related conditions such as capsule rupture or tear and 7 days for 

more general medical conditions, such as arrhythmia. Sixteen of the procedures 

received moderate to high ratings for both preventability and severity. These are shown 

in bold type in Table 5.9 below. 

EMPIRICAL EVALUATION 

The results of the claims analyses for cataract surgery are shown in Tables 5.1 

through 5.9, based on a 5 percent sample of beneficiaries. A total of 77,572 cataract 

surgeries were performed for Medicare beneficiaries in the 5 percent sample during 

CY2001 (Table 5.1). Of cataract surgeries performed in an ambulatory setting, more 

than half are done in an ASC (52 percent). Most of the remaining procedures are 

performed in an HOPD (47 percent), with less than 1 percent done in an office setting. 

Of the cataract surgeries done in an HOPD, a slightly higher percentage are female, 

age 85 and over, African-American, originally disabled, or Medicaid-eligible compared to 

ASC surgeries. 

In all geographic regions of the United States except the Mountain region, 

between 40 and 60 percent of cataract surgeries are performed in an HOPD (Table 

5.2), with most of the remaining procedures done in an ASC. In the Mountain region, 

however, the percentage is much lower in the HOPD (27 percent) and much higher in 

the ASC (73 percent). In all regions, less than one percent of cataract surgeries are 

performed in a physician office. 

Procedure Characteristics 

In the three settings combined, less than 2 percent of the cataract surgery claims 

in this 2001 sample had more than one cataract surgery within BETOS P4B coded 

(Table 5.3). This pattern of care differed among settings, however, from under 1 

percent of the HOPD claims to almost 12 percent of office claims having more than one 
40 

cataract surgery code. Of the claims with one procedure, over 96 percent of cataract 

surgeries performed in any ambulatory setting are coded as 66984 [Extracapsular 

cataract removal with insertion of intraocular lens prosthesis (one stage procedure), 

manual or mechanical] (Table 5.3). This one HCPCS code accounts for a slightly lower 

percentage of cataract surgeries in the office setting (76 percent) than in the other two 

settings. Among those records with two or more cataract surgery codes, the two codes 

are usually the same (e.g., 66984 and 66984) and probably result from separate claims 

for surgical care only and pre-and post-operative care. 

Ophthalmologists performed most cataract surgeries, with 88 percent in the 

HOPD, 92 percent in the ASC, and 77 percent in the office (Table 5.4). Optometrists 

performed many of the remaining cataract procedures in the three settings, from 2 

percent in the HOPD to 22 percent in the office setting (which are likely to have been for 

pre-and/or post-surgical care only). A higher percentage of professional claims for ASC 

cataract surgeries reported a modifier indicating only surgical care was provided and 

another physician provided pre-and post-surgical care (16 percent) than in HOPDs (12 

percent) and office (8 percent) (data not shown). One percent of HOPD cataract 

surgeries were reported as being performed by a resident under the supervision of a 

teaching physician compared to a few in ASCs (data not shown). 

The roles of anesthesiologists and certified nurse anesthetists/anesthesia 

assistants differed between HOPDs and ASCs for CPT code 66984 (Table 5.5). The 

specialty for anesthesia line items was reported as anesthesiology 55 percent of the 

time in HOPDs compared to 45 percent of the time in ASCs while certified registered 

nurse anesthetist (CRNA)/anesthesia assistant was the reported specialty for 42 

percent and 52 percent of the anesthesia line items for HOPD and ASC surgeries, 

respectively. 

An anesthesiologist may personally provide the anesthesia care or may direct 

CRNAs in up to 4 procedures concurrently. A CRNA may work independently or under 

the supervision of an anesthesiologist. Modifiers are used to describe the relative roles 

of the anesthesiologist and CRNA in the anesthesia care provided to a beneficiary. 

Even though a higher percentage of anesthesiologists are involved in a beneficiary’s 

care in HOPDs, the reported modifiers indicate anesthesiologists personally furnished a 
41 

smaller proportion of anesthesia for CPT code 66984 in HOPDs than ASCs (24 percent 

compared to 30 percent) and provide medical direction of CRNAs in a higher proportion 

of surgeries performed in HOPDs. CRNAs worked without medical direction from a 

physician 14 percent of the time in HOPDs, compared to 35 percent of the time in 

ASCs. 

Table 5.1 Characteristics of Beneficiaries With Cataract Surgery (BETOS P4B) By Ambulatory 

Setting, Medicare Fee-for-Service, 2001 

Characteristic

N %* N %* N %* N %*

Total 36,623 100.00 40,671 100.00 278 100.00 77,572 100.00

Male 12,838 35.1 15,204 37.4 102 36.7 28,144 36.3

Female 23,784 64.9 25,461 62.6 176 63.3 49,421 63.7

Age in years at time of procedure

Under 65 1,257 3.4 1,165 2.9 11 4.0 2,433 3.1

65-69 4,938 13.5 5,901 14.5 41 14.7 10,880 14.0

70-74 8,544 23.3 10,087 24.8 58 20.9 18,689 24.1

75-79 10,347 28.3 11,668 28.7 75 27.0 22,090 28.5

80-84 7,308 20.0 7,820 19.2 57 20.5 15,185 19.6

85 and Over 4,229 11.5 4,030 9.9 36 12.9 8,295 10.7

White 32,698 89.3 37,228 91.5 228 82.0 70,154 90.4

African-American 2,534 6.9 1,954 4.8 32 11.5 4,520 5.8

Other 1,391 3.8 1,489 3.7 18 6.5 2,898 3.7

Originally disabled 3,701 10.1 3,641 9.0 26 9.4 7,368 9.5

Medicaid eligible for 1 or more months 4,966 13.6 4,321 10.6 45 16.2 9,332 12.0

End-stage renal disease 327 0.9 325 0.8 7 2.5 659 0

Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

*Numbers in this column represent percentages of column total.

HOPD ASC Office All Sites

.8
42 

Table 5.2 Percentage of Cataract Surgeries (BETOS P4B) Performed In Three Ambulatory Settings By Geographic AService System, 2001

Census Region***

N %* N %* N %* 

Total 36,623 47.2 40,671 52.4 278 0.4 7New England 2,063 54.9 1,685 44.9 8 0.2 3Middle Atlantic 4,977 50.4 4,864 49.2 42 0.4 9East North Central 7,737 56.2 6,006 43.6 26 0.2 1West North Central 3,856 58.4 2,720 41.2 22 0.3 6South Atlantic 7,041 41.5 9,853 58.1 71 0.4 1East South Central 2,783 44.0 3,505 55.4 37 0.6 6West South Central 3,552 41.2 5,033 58.4 27 0.3 8Mountain 1,125 26.5 3,106 73.1 18 0.4 4Pacific 3,191 48.1 3,419 51.5 23 0.3 6*Numbers in this column represent percentages of row total.**Numbers in this column represent percentages of column total.***New England: Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, Vermont

Middle Atlantic: New Jersey, New York, PennsylvaniaEast North Central: Illinois, Indiana, Michigan, Ohio, WisconsinWest North Central: Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, South DakotaEast South Central: Alabama, Kentucky, Mississippi, TennesseeWest South Central: Arkansas, Louisiana, Oklahoma, TexasMountain: Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, WyomingPacific: Alaska, California, Hawaii, Oregon, Washington

Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

HOPD ASC Office 

South Atlantic: Delaware, District of Columbia, Florida, Georgia, Maryland, North Carolina, South Carolina, Virginia, 
43 

Table 5.3 Distribution of Cataract Surgeries (BETOS P4B)* By HCPCS and Number of Procedures 

Coded for Same Day By Ambulatory Setting, Medicare Fee-for-Service, 2001 

N %** N %** N %** N %**

Total 36560 100 40671 100 265 100 77496 100

One procedure 36283 99.2 39703 97.6 234 88.3 76220 98.4

66830 Removal of secondary membranous cataract 

(opacified posterior lens capsule and/or anterior

hyaloid) with corneo-scleral section, with or without 

iridectomy (iridocapsulotomy, iridocapsulectomy).

31 0.1 2 0.0 21 7.9 54 0.1

66840 Removal of lens material; aspiration technique, one 

or more stages.

12 0 31 0.1 0 0 43 0.1

66850 Removal of lens material; phacofragmentation

technique (mechanical or ultrasonic) (eg,

phacoemulsification), with aspiration.

72 0.2 45 0.1 1 0.4 118 0.2

66852 Removal of lens material; pars plana approach,

with or without vitrectomy.

58 0.2 12 0.0 0 0 70 0.1

66920 Removal of lens material; intracapsular. 26 0.1 0 0.0 0 0 26 0

66930 Removal of lens material; intracapsular, for

dislocated lens.

20 0.1 5 0.0 0 0 25 0

66940 Removal of lens material; extracapsular (other than

66840, 66850, 66852).

32 0.1 13 0.0 0 0 45 0.1

66982 Cataract surgery, complex (Not in manual) 314 0.9 198 0.5 5 1.9 517 0.7

66983 Intracapsular cataract extraction with insertion of

intraocular lens prosthesis (one stage procedure).

126 0.3 80 0.2 0 0 206 0.3

66984 Extracapsular cataract removal with insertion of

intraocular lens prosthesis (one stage procedure),

manual or mechanical technique (eg, irrigation and 

aspiration or phacoemulsification).

35330 96.6 39045 96 201 75.8 74576 96.2

66985 Insertion of intraocular lens prosthesis (secondary

implant), not associated with concurrent cataract 

removal.

120 0.3 149 0.4 4 1.5 273 0.4

66986 Exchange of intraocular lens. 142 0.4 123 0.3 2 0.8 267 0.3

Two procedures 272 0.7 856 2.1 20 7.6 1148 1.5

Three procedures 5 0 82 0.2 8 3 95 0.1

Four procedures 0 0 18 0 3 1.1 21 0

Five procedures 0 0 12 0 0 0 12 0

lens capsule and/or anterior hyaloid); stab incision technique (Ziegler or Wheeler knife)).

Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

*Excluded from this table are 77 procedures coded as 66820 (Discission of secondary membranous cataract (opacified posterior

**Numbers in this column represent percentages of column total.

HOPD ASC Office All Sites
44 

Table 5.4 Top Five Specialties* of Providers Performing Cataract Surgery (BETOS P4B) By 

Ambulatory Setting, Medicare Fee-for-Service System, 2001 

Setting Specialty Code Specialty Description Number Percent**

HOPD 18 Ophthalmology 32,138 87.8

70 Multispecialty clinic or group practice 1,073 2.9

41 Optometry 838 2.3

12 Osteopathinc manipulative therapy 17 0.0

26 Psychiatry 15 0.0

ASC 18 Ophthalmology 37,458 92.1

41 Optometry 1,227 3.0

70 Multispecialty clinic or group practice 844 2.1

4 Otolaryngology 51 0.1

79 Addiction medicine 36 0.1

Office*** 18 Ophthalmology 214 77.0

41 Optometry 60 21.6

70 Multispecialty clinic or group practice 3 1.1

26 Psychiatry 1 0.4

***Only four specialties were listed on the claims for office procedures.

Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

*Specialties were derived from the claims for professional services associated with the procedure.

**Numbers in this column represent percentages of all procedures performed in the indicated setting. 

The percentages do not total 100 percent because they represent only the top five specialties. 
45 

Table 5.5 Anesthesia Services Related to Cataract Surgery By Ambulatory Setting, Medicare Feefor-Service System, 2001 

Specialty 

Code Specialty All Settings HOPD ASC

5 Anesthesiology 51.0 54.9 46.4

43 CRNA/ Anesthesia assistant 46.7 42.1 52.1

70 Multispecialty clinic or group practice 1.5 2.3 0.6

Various Other 0.8 0.7 1.0

HCPCS 

Modifier

Code

Description All Settings HOPD ASC

QS Monitored anesthesia care service 52.4 55.8 48.3

AA Anesthesia services personally performed

by anesthesiologist 27.1 24.3 30.4

QZ CRNA service: without medical direction 

by a physician

23.4 13.5 35.2

QX CRNA service: medical direction by a

physician 22.7 28.6 15.5

QK Medical direction 2-4 concurrent 

procedures

20.2 27.3 11.8

QY Clinical nurse specialist; team member 3.2 3.1 3.4

AD Medical supervision by physician: more

than 4 concurrent procedures

0.7 1.0 0.3

Source: RAND analysis of the 5% standard Analytic Files of Medicare Claims, 2001. 

% of Anesthesia Line Items

indicated setting that had an anesthesia claim.

*Numbers in the columns represent percentages of all procedures performed in the

Patient Characteristics 

For the most frequently performed procedure (CPT 66984), the average HCC 

risk score is highest among patients having cataract surgery in the office (1.36) followed 

by patients in an HOPD (1.21) and an ASC (1.14) (Table 5.6). This pattern among the 

three settings also holds for several of the other cataract surgery categories. 

In the HOPD, ASC, and office, the most frequently coded diagnosis on facility 

claims for cataract surgery is senile nuclear cataract (ICD-9-CM 366.16), accounting for 
46 

34 to 49 percent of the procedures. Several other cataract diagnoses are coded with 

widely varying frequency in the three sites21 (Table 5.7). Two co-morbid diagnoses, 

hypertension (ICD-9-CM 401.9) and diabetes mellitus (ICD-9-CM 250.00), were coded 

much more frequently on HOPD facility claims than on ASC or office claims. 

The prevalence rates of 17 characteristics that might increase the risk of an 

adverse outcome among patients (i.e., risk factors) having cataract surgery are shown 

in Table 5.8.22 Each characteristic was identified using all claims for care received by 

the patient in any inpatient or outpatient setting during the months and days of 2001 

preceding the date of the cataract surgery. The prevalence rates are consistently 

higher for all 17 risk factors among patients having the cataract surgery in an HOPD 

than in an ASC. Although based on extremely small numbers, the prevalence rates of 

some risk factors are even higher among the office patients than among the HOPD 

patients. 

Outcomes 

Adverse outcomes occurred at a low rate following cataract surgery (Table 5.9). 

Most outcomes occurred more frequently among HOPD patients than among ASC 

patients. Although the office-based outcome rates are based on very small numbers of 

events, they are higher than rates in the other two settings. This finding warrants further 

study. 

 21 The diagnoses for the office setting are derived from the professional, rather than the facility, claim.

22 As mentioned in the Methods section, the cataract surgery panel rated these characteristics with a 

median of 4 or higher on a 1-to-9 risk scale, with 9 being high risk.
47 

SUMMARY OF FINDINGS 

About 97 percent of procedures within this BETOS category were for a single 

HCPCS code. Detecting differences in the procedure across settings is problematic 

because of billing requirements for anesthesia time and materials and bundling of 

intraocular lenses into the facility payment. It is possible, however, to measure 

differences in who is providing anesthesia and whether one or more physicians are 

involved in the patient’s care. On the issue of patient characteristics, the panel ratings 

and discussion indicated that these are low risk procedures that can be safely 

performed in either an HOPD or ASC. Nevertheless, there are differences in the patient 

characteristics. The average HCC risk score is higher among patients having cataract 

surgery in an HOPD (1.21) than an ASC (1.14) and the prevalence rates are 

consistently higher for all 17 risk factors among patients having the cataract surgery in 

an HOPD than in an ASC. Adverse outcomes occurred at a low rate following cataract 

surgery. The analyses found few cataract procedures are performed in physician 

offices, but the rate of adverse outcomes for these procedures suggests that further 

investigation might be warranted. 
48 

Table 5.6 Average Risk Scores With Cataract Surgery (BETOS P4B) By Ambulatory Setting, 

Medicare Fee-for-Service System, 2001

HCPCS HCPCS Description HOPD ASC Office All Sites 

All Cataract 1.21 1.14 1.39 1.17

66820 Discission of secondary membranous cataract (opacified posterior lens 

capsule and/or anterior hyaloid); stab incision technique (Ziegler or

Wheeler knife).

1.08 NA 1.69 1.18

66830 Removal of secondary membranous cataract (opacified posterior lens 

capsule and/or anterior hyaloid) with corneo-scleral section, with or without

iridectomy (iridocapsulotomy, iridocapsulectomy).

1.17 2.19 1.48 1.33

66840 Removal of lens material; aspiration technique, one or more stages. 1.03 1.20 NA 1.16

66850 Removal of lens material; phacofragmentation technique (mechanical or

ultrasonic) (eg, phacoemulsification), with aspiration.

1.56 1.14 2.69 1.42

66852 Removal of lens material; pars plana approach, with or without vitrectomy. 1.34 0.78 NA 1.22

66920 Removal of lens material; intracapsular. 1.35 NA NA 1.35

66930 Removal of lens material; intracapsular, for dislocated lens. 1.33 0.66 NA 1.23

66940 Removal of lens material; extracapsular (other than 66840, 66850, 66852). 1.26 1.40 NA 1.30

66982 Cataract surgery, complex (Not in manual) 1.24 1.35 1.07 1.28

66983 Intracapsular cataract extraction with insertion of intraocular lens 

prosthesis (one stage procedure). 1.43 0.98 NA 1.25

66984 Extracapsular cataract removal with insertion of intraocular lens prosthesis

(one stage procedure), manual or mechanical technique (eg, irrigation and 

aspiration or phacoemulsification).

1.20 1.14 1.36 1.17

66985 Insertion of intraocular lens prosthesis (secondary implant), not associated 

with concurrent cataract removal. 1.54 1.21 1.98 1.36

66986 Exchange of intraocular lens. 1.12 1.29 0.74 1.20

NA=Not available; zero patients in cell.

Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.
49 

Table 5.7 Top Ten Diagnoses on Facility Claim* for Cataract Surgery (BETOS P4B) By Ambulatory Setting, Medicare 

System, 2001 

ICD-9 Code ICD-9 Code Description

N %** N %** N %** 

366.16 Senile nuclear cataract 12,452 34.0 19,957 49.1 106 38.1 

366.9 Cataract NOS 11,924 32.6 4,785 11.8 12 4.3 401.9 Essential hypertension, unspecified 12,209 33.3 892 2.2 4 1.4 366.1 Senile cataract NOS 4,391 12.0 5,977 14.7 47 16.9 

366.17 Mature Cataract 2,336 6.4 3,728 9.2 18 6.5 366.19 Senile Cataract NEC 2,202 6.0 2,852 7.0 26 9.4 

250 DM w/o compl, type II or unspecified type,

not stated as uncontrolled 3,714 10.1 330 0.8 5 1.8 

366.15 Cortical senile cataract 1,170 3.2 2,083 5.1 20 7.2 366.14 Post subcap senile cataract 1,402 3.8 1,719 4.2 8 2.9 

366.8 Cataract NEC 1,818 5.0 201 0.5 1 0.4 

*Diagnoses for physician office procedures were derived from professional claims.

Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

**Numbers in this column represent percentages of all procedures performed in the indicated setting. The sum of the 

HOPD ASC Office 

exceed 100 percent because multiple diagnoses can be coded on a single claim.
50 

Table 5.8 Selected Risk Factors of Beneficiaries With Cataract Surgery (BETOS P4B) By Ambulatory 

Setting, Medicare Fee-for-Service System, 2001 

 Indicator*

N Rate** N Rate** N Rate** N Rate**

N Cardiomyopathy/heart failure/pulmonary

edema with hospitalization or

emergency department visit within past 

2,048 55.9 1,615 39.7 24 86.3 3,687 47.5

I Dementia 360 9.8 172 4.2 8 28.8 540 7.0

BF Dislocation of lens 265 7.2 184 4.5 1 3.6 450 5.8

AG Persistent severe sinus bradycardia or

sick sinus tachycardia-bradycardia

syndrome

254 6.9 192 4.7 3 10.8 449 5.8

G Myocardial infarction (>30 days but 

fewer than 6 months) 149 4.1 124 3.0 4 14.4 277 3.6

D Unstable angina in last 3 months 173 4.7 99 2.4 3 10.8 275 3.5

X Malignant hypertension 130 3.5 125 3.1 4 14.4 259 3.3

AC Paroxysmal Ventricular Tachycardia 134 3.7 90 2.2 1 3.6 225 2.9

Y Primary pulmonary hypertension 54 1.5 26 0.6 0 0.0 80 1.0

BD Pseudoexfoliation of lens capsule 40 1.1 6 0.1 3 10.8 49 0.6

F Recent myocardial infarction (> 7 days 

but fewer than 30 days) 29 0.8 16 0.4 0 0.0 45 0.6

BJ Posterior synechiae 19 0.5 4 0.1 0 0.0 23 0.3

BB Subluxation of lens 12 0.3 7 0.2 0 0.0 19 0.2

E Myocardial infarction within past 7 days 9 0.2 4 0.1 0 0.0 13 0.2

BE Progressive high (degenerative)

myopia/malignant myopia 7 0.2 1 0.0 0 0.0 8 0.1

AS History of shock due to anesthesia in

which correct substance was properly

administered

1 0.0 0 0.0 0 0.0 1 0.0

BC Recession of chamber angle 1 0.0 0 0.0 0 0.0 1 0.0

**Per 1,000 procedures.

Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

HOPD ASC Office All Sites 

*Letter codes in this column are taken from the rating form for the RAND expert panel. (Refer to Appendix C)
51 

Table 5.9 Selected Outcomes Occurring Within 30 Days Following Cataract Surgery (BETOS P4B) 

By Ambulatory Setting, Medicare Fee-for-Service System, 2001 

Outcome***

N* Rate** N* Rate** N* Rate** N* Rate**

Other complications  394 10.8 141 3.5 5 18.0 540 7.0

Stroke 286 7.8 195 4.8 3 10.8 484 6.2

Retained nuclear fragment (posterior

chamber v anterior chamber) 214 5.8 255 6.3 4 14.4 473 6.1

Myocardial infarction 131 3.6 93 2.3 5 18.0 229 3.0

Nausea and vomiting 123 3.4 75 1.8 2 7.2 200 2.6

Secondary glaucoma 124 3.4 28 0.7 2 7.2 154 2.0

Arrythmia 105 2.9 42 1.0 3 0.0 150 1.9

Endophthalmitis 65 1.8 47 1.2 1 3.6 113 1.5

Dislocated ocular lenses 75 2.0 31 0.8 2 7.2 108 1.4

Cataract fragments in eye 49 1.3 41 1.0 2 7.2 92 1.2

Iris prolapse 46 1.3 16 0.4 0 0.0 62 0.8

Hypotension 30 0.8 28 0.7 1 3.6 59 0.8

Retinal detachment (complicated v

uncomplicated surgery) 39 1.1 19 0.5 0 0.0 58 0.7

Persistent corneal edema 28 0.8 25 0.6 1 3.6 54 0.7

Vitreous loss 30 0.8 20 0.5 4 14.4 54 0.7

Persistent iridocyclitis 28 0.8 12 0.3 1 3.6 41 0.5

Respiratory failure from surgery 16 0.4 5 0.1 1 3.6 22 0.3

Hyphema 13 0.4 7 0.2 0 0.0 20 0.3

Persistent cystoid macular edema 

(Diabetic v non-diabetic) 13 0.4 5 0.1 0 0.0 18 0.2

Aspiration pneumonia 7 0.2 9 0.2 0 0.0 16 0.2

Ocular hypertension 5 0.1 5 0.1 0 0.0 10 0.1

Retinal break 1 0.0 6 0.1 0 0.0 7 0.1

Hypertension 1 0.0 2 0.0 0 0.0 3 0.0

** Per 1,000 procedures.

excluding cranial VII palsy.

No cases were found where death, poor ocular motility, or iris/pupil deformation were reported as a complication.

Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

HOPD ASC Office All Sites

device, implant, and graft, 998.0-998.9 (Other complications of procedures NEC) and V45.6 (States following

eye surgery: Cataract extractor, Filtering bleb, Surgical eyelid adhesion -Excludes: aphakia (379.31) artificial: 

eye globe (V43.0) lens (V43.1)). 

***Outcomes shown in bold were rated at least moderately severe amd somewhat preventable by the cataract

**** Other complications are diagnosis codes 996.5 (Mechanical complications of other specified prosthetic 

*Numbers in this column represent the number of outcomes.

expert panel. The panel also gave these ratings to death, wound leak, iris/pupil deformation, and poor ocular motility, 

53 

6. COLONOSCOPY 

In this section, we summarize the results from the expert panel and our empirical 

evaluation of administrative data for colonoscopy procedures. Colonoscopy is a 

commonly performed procedure used to screen for colorectal cancer but it is also used to 

diagnose the causes of symptoms such as bleeding or unexplained changes in bowel 

habits, which may be caused by cancer or some other disease/condition. Therapeutic 

colonoscopies can be performed to remove polyps and to treat bleeding in the colon. 

Generally, the procedure is performed under some level of sedation and/or with pain 

medication. In 2001, colonoscopies accounted for about 1.1 percent of Medicare’s volume 

and 4.4 percent of its payments for ambulatory procedures (exclusive of anesthesia and 

evaluation and management services, outpatient rehabilitation services and laboratory 

tests).23 Colonoscopy was selected as a study procedure because it is a high volume 

surgical procedure performed in three ambulatory settings: HOPDs, ASCs, and physician 

offices. 

Most colonoscopies are uncomplicated and effectively diagnose and treat various 

gastrointestinal conditions. In some cases however, intra-operative and post-operative 

complications arise including most commonly perforation, bleeding, pain, and abdominal 

discomfort. Complications unrelated to the colon but often associated with sedation 

include:oxygen desaturation, hypertension, hypotension, arrhythmias, and bradycardia. 

Complications of the colonoscopy procedure may lead to hospitalization and in rare 

cases, death. 

EXPERT PANEL RESULTS 

The results of the expert panel rankings for all measures are shown in Appendix 

D. In this section, we summarize the results and highlight those that suggested 

differences in patient characteristics, procedure characteristics, or outcomes for 

colonoscopies performed across the three ambulatory settings. 

 23 This calculation does not include DME, drugs and medical supplies, and outpatient dialysis and 

accounts only for professional and facility services provided in physician offices, ASCs, HOPDs, and IDTFs. 
54 

Patient Characteristics 

The expert panel was asked to rate the relative risk of performing a colonoscopy 

on patients with particular conditions. The risk of performing the procedure in any of the 

settings was most often rated low and there were only slight differences in the ratings 

across the settings. As a general pattern, the median rating for physician offices was 

higher than for either hospital outpatient settings or ASCs. However, there was no 

agreement on the appropriateness rating for physician office for a number of conditions, 

i.e., at least two members rated the procedure as relatively low-risk while at least two 

others rated the procedure as relatively high risk. The ratings may reflect differences in 

panelist assumptions regarding whether staffing and resources in physician office 

performing colonoscopies are comparable to those in ASCs. This issue was raised during 

the panel discussion. 

For some conditions (e.g., recent myocardial infarction more than 30 days ago 

but within 6 months) performing the procedure in ASCs was rated as posing slightly less 

risk than HOPDs, while the converse occurred for other conditions (e.g., COPD with 

hospitalization or emergency department visit within past one year). In their discussions, 

the panelists appeared to be weighing the benefits of having immediately available 

emergency services versus generally less stressful patient environment in an ASC. 

No conditions were rated as posing high risk in any of the settings. The ratings 

were inconclusive or reflected no agreement for several conditions in at least two sites: 

myocardial infarction within the past 7 days, orthopnea, persistent severe sinus 

bradycardia or sick sinus tachycardia-bradycardia syndrome, orthostatic hypotension and 

malignant hypertension. 

Procedure Characteristics 

 The colonoscopy panel was asked to rate the appropriateness of 

performing various types of colonoscopies in the different settings on patients at three risk 

levels: normal or very low risk, low-moderate risk, and moderate risk. For HOPDs, all 

procedures were rated as highly appropriate with the exception of colonoscopies with 

dilation of stricture without fluoroscopy, which had an inconclusive rating across all three 

patient risk levels. Colonoscopy with dilation of the stricture with fluoroscopy also had 
55 

inconclusive ratings in ASCs. Other procedures with inconclusive ratings in ASCs were: 

colonoscopy with lesion removal or with endoscopic mucosal resection (all patient risk 

categories); colonoscopy with stent (low-moderate and moderate risk patients); and 

colonoscopy with submucuous injection (moderate risk patients). 

The appropriateness ratings for colonoscopies performed in physician offices 

reflect disagreement within the panel on whether the procedures should be performed in 

this setting. There was either no agreement or an inconclusive rating on nearly all 

procedures. The panel members agreed that the following procedures were appropriately 

performed on patients with normal to low-moderate risk in a physician office: colonoscopy 

with biopsy, colonoscopy with polypectomy involving the ascending colon, and 

colonoscopy with snare. 

Outcomes 

The colonoscopy panel was asked to rate 19 potential outcomes associated with 

a colonoscopy on two dimensions: preventability and severity. There was agreement that 

chest pain was moderately preventable; there was either no agreement or inconclusive 

preventability ratings for the remaining outcomes. There was agreement that a number of 

outcomes were moderately or quite severe. These were: death, hemorrhage, hypoxia, 

perforation, post-polypectomy syndrome, endocarditis, sepsis, small bowel obstruction, 

splenic rupture or trauma, and vasovagal reactions. 

EMPIRICAL EVALUATION RESULTS 

The results of the claims analyses for colonoscopy are shown in Tables 6.1 

through 6.8. Based on a 5 percent sample of beneficiaries, a total of 90,890 

colonoscopies were performed for Medicare beneficiaries during CY2001 (Table 6.1). Of 

colonoscopies performed in an ambulatory setting, most were done in an HOPD (70 

percent). Most of the remaining procedures are performed in an ASC (26 percent), with 4 

percent done in an office. The distributions of colonoscopies by age, gender, and race 

are similar for procedures in the three settings. Of the colonoscopies done in an HOPD, 

slightly higher percentages are originally disabled or dual eligible beneficiaries compared 

to ASC colonoscopies. 
56 

Most geographic regions in the United States show similar distributions of 

colonoscopy by setting, with 60 to 70 percent performed in an HOPD and another 30 to 

40 percent in an ASC (Table 6.2). The exceptions to this pattern are New England, East 

North Central, and West North Central with more colonoscopies performed in the HOPD, 

and the Middle Atlantic with more procedures done in an office setting. 

Table 6.1 Characteristics of Beneficiaries with Colonoscopy (BETOS P8D) By Ambulatory Setting, 

Medicare Fee-for-Service System, 2001 

Characteristic

N %* N %* N %* N %*

Total 63,372 100.00 23,503 100.00 4,015 100.00 90,890 100.00

Male 27,658 43.7 10,241 43.6 1,809 45.1 39,708 43.7

Female 35,703 56.3 13,260 56.4 2,206 54.9 51,169 56.3

Age in years at time of procedure

Under 65 5,578 8.8 1,593 6.8 323 8.0 7,494 8.2

65-69 15,038 23.7 6,066 25.8 1,022 25.5 22,126 24.3

70-74 17,023 26.9 6,505 27.7 1,154 28.7 24,682 27.2

75-79 13,971 22.0 5,416 23.0 876 21.8 20,263 22.3

80-84 8,194 12.9 2,792 11.9 459 11.4 11,445 12.6

85 and Over 3,568 5.6 1,131 4.8 181 4.5 4,880 5.4

White 56,980 89.9 21,313 90.7 3,433 85.5 81,726 89.9

African-American 4,480 7.1 1,453 6.2 301 7.5 6,234 6.9

Other 1,912 3.0 737 3.1 281 7.0 2,930 3.2

Originally disabled 9,540 15.1 2,782 11.8 574 14.3 12,896 14.2

Medicaid eligible for 1 or more months 7,222 11.4 1,965 8.4 333 8.3 9,520 10.5

End-stage renal disease 427 0.7 125 0.5 23 0.6 575 0.6

*Numbers in this column represent percentages of column total.

Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

HOPD ASC Office All Sites
57 

Table 6.2 Percentage of Colonoscopies (BETOS P8D) Performed in Three Ambulatory Settings By 

Geographic Area, Medicare Fee-for-Service, 2001 

 Census Region***

N %* N %* N %* N %**

Total 63,372 69.7 23,503 25.9 4,015 4.4 90,890 100.00

New England 4,211 86.5 607 12.5 48 1.0 4,866 5.4

Middle Atlantic 9,393 69.1 2,143 15.8 2,050 15.1 13,586 14.9

East North Central 12,258 78.2 3,147 20.1 261 1.7 15,666 17.2

West North Central 5,740 81.5 1,125 16.0 182 2.6 7,047 7.8

South Atlantic 13,238 63.0 7,215 34.3 574 2.7 21,027 23.1

East South Central 4,627 69.6 1,960 29.5 65 1.0 6,652 7.3

West South Central 6,163 68.8 2,666 29.8 129 1.4 8,958 9.9

Mountain 2,641 61.5 1,537 35.8 117 2.7 4,295 4.7

Pacific 4,794 59.6 3,023 37.6 223 2.8 8,040 8.8

*Numbers in this column represent percentages of row total.

**Numbers in this column represent percentages of column total.

***New England: Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, Vermont

Middle Atlantic: New Jersey, New York, Pennsylvania

East North Central: Illinois, Indiana, Michigan, Ohio, Wisconsin

West North Central: Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, South Dakota

South Atlantic: Delaware, DC, Florida, Georgia, Maryland, N. Carolina, S. Carolina, Virginia, W. Virginia

East South Central: Alabama, Kentucky, Mississippi, Tennessee

West South Central: Arkansas, Louisiana, Oklahoma, Texas

Mountain: Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, Wyoming

Pacific: Alaska, California, Hawaii, Oregon, Washington

Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

HOPD ASC Office All Sites
58 

 

Procedure Characteristics 

In all three sites combined, 54 percent of colonoscopies involved some lesion 

removal, biopsy, or control of bleeding (RBC) procedures while the remaining 46 

percent were non-RBC procedures (Table 6.3). The pattern of more RBC 

colonoscopies holds for the HOPD or ASC settings, but in the office setting, more nonRBC colonoscopies (53 percent) than RBC colonoscopies (47 percent) were done. In 

the three settings combined, 8 percent of the claims in this 2001 sample had more than 

one colonoscopy within BETOS P8D coded on the same day (Table 6.3). The 

percentage with more than one colonoscopy code was similar across settings. 24 

Of the claims with one procedure, four CPT codes account for most of the 

colonoscopies: 45378, 45385, 45380, and 45384 (see Appendix for definitions). Among 

those records with two or more colonoscopy codes, the most common combinations are 

biopsy/removal of lesion by hot biopsy forceps or bipolar cautery (45380/45384), 

biopsy/removal of lesion by snare technique (45380/45385), and removal of lesion by 

hot biopsy forceps or bipolar cautery/ removal of lesion by snare technique 

(45384/45385). 

Gastroenterologists performed a higher percentage of the colonoscopies in ASCs 

(72 percent) than in HOPDs (46 percent) or offices (67 percent) (Table 6.4). In HOPDs, 

most of the remaining colonoscopies were done by a general surgeon (12 percent) or 

an internist (8 percent). Internists performed most of the remaining colonoscopies in 

ASCs (6 percent) and offices (15 percent), with a smaller percentage of procedures 

being performed by a general surgeon in ASCs and offices (4 and 5 percent, 

respectively). 

24 Modifier codes distinguish between multiple procedures that are performed on the same day or at the 

same session by the same provider (-51) and those that are distinct or independent from other procedures 

performed on the same day (-59). The percentage of claims that were coded with multiple procedures 

exceeded the percentage of claims that used either modifier –51 or –59, which suggests that the modifier 

codes may not be a reliable way to identify distinct procedures. For example, only 6 percent of the claims for 

professional services reported either multiple procedures (4 percent) or distinct procedures (2 percent). 

Modifiers were coded less frequently on the facility claims than the professional claims for procedures 

performed in OPDs and ASCs.
59 

Table 6.3 Distribution of Colonoscopies (BETOSP8D) and Number of Procedures Coded for Same Day By 

Ambulatory Setting, Medicare Fee-for-Service, 2001 

HCPCS HCPCS Description

N %* N %* N %* N %*

All Colonoscopy 63372 100 23503 100 4015 100 91190 100

Non-RBC colonoscopy** 29035 45.8 10520 44.8 2133 53.1 41688 45.7

RBC colonoscopy*** 34337 54.2 12983 55.2 1882 46.9 49202 54

One procedure 58208 91.9 21338 90.8 3669 91.4 83215 91.6

44388 Colonoscopy through stoma; diagnostic, with or without 

collection of specimen(s) by brushing or washing (separate 

procedure).

221 0.3 35 0.1 7 0.2 263 0.3

44389 Colonoscopy through stoma; with biopsy, single or multiple. 58 0.1 7 0 0 0 65 0.1

44391 Colonoscopy through stoma; with control of bleeding, any 

method.

1 000 0 0 1 0

44392 Colonoscopy through stoma; with removal of tumor(s), 

polyp(s), or other lesion(s) by hot biopsy forceps or bipolar 

cautery.

49 0.1 7 0 1 0 57 0.1

44393 Colonoscopy through stoma; with ablation of tumor(s), 

polyp(s), or other lesion(s) not amenable to removal by hot 

biopsy forceps, bipolar cautery or snare technique.

12 000 0 0 12 0

44394 Colonoscopy through stoma; with removal of tumor(s), 

polyp(s), or other lesion(s) by snare technique.

53 0.1 4 0 0 0 57 0.1

45378 Colonoscopy, flexible, proximal to splenic flexure; diagnostic, 

with or without collection of specimen(s) by brushing or

washing, with or without colon decompression (separate 

procedure).

26921 42.5 9160.0 39.0 1914.0 47.7 37995 41.8

45379 Colonoscopy, flexible, proximal to splenic flexure; with 

removal of foreign body.

15 060 4 0.1 25 0

45380 Colonoscopy, flexible, proximal to splenic flexure; with 

biopsy, single or multiple.

8472 13.4 3662 15.6 584 14.5 12718 14

45382 Colonoscopy, flexible, proximal to splenic flexure; with control

of bleeding, any method.

120 0.2 56 0.2 10 0.2 186 0.2

45383 Colonoscopy, flexible, proximal to splenic flexure; with 

ablation of tumor(s), polyp(s), or other lesion(s) not amenable 

to removal by hot biopsy forceps, bipolar cautery or snare 

technique.

1629 2.6 368 1.6 54 1.3 2051 2.3

45384 Colonoscopy, flexible, proximal to splenic flexure; with 

removal of tumor(s), polyp(s), or other lesion(s) by hot biopsy 

forceps or bipolar cautery.

7023 11.1 2390 10.2 213 5.3 9626 10.6

45385 Colonoscopy, flexible, proximal to splenic flexure; with 

removal of tumor(s), polyp(s), or other lesion(s) by snare 

technique.

11996 18.9 4796 20.4 792 19.7 17584 19.3

45387 Colonoscopy, flexible, proximal to splenic flexure; with 

transendoscopic stent placement (includes predilation)

4 000 0 0 4 0

G0105 Colorectal screen; high risk individual 1634 2.6 847 3.6 90 2.2 2571 2.8

Two procedures 4866 7.7 1891 8.1 298 7.4 7055 7.8

Three procedures 271 0.4 178 0.8 39 1 488 0.5

Four procedures 19 0 71 0.3 4 0.1 94 0.1

Five procedures 6 0 25 0.1 5 0.1 36 0

Six procedures 2 000 0 0 2 0

Total 63372 100 23503 100 4015 100 90890 100

*Numbers in this column represent percentages of column total.

**Non-RBC colonoscopy includes HCPCS 44388, 45378, and G0105. 

***RBC colonoscopy includes HCPCS 44389, 44391, 44392, 44393, 44394, 45379, 45380, 45382, 45383, 45384, 45385, and 45387.

All Sites

Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

HOPD ASC Office
60 

Table 6.4 Top Five Specialties* of Providers Performing Colonoscopy (BETOS P8D) By Ambulatory 

Setting, Medicare Fee-for-Service System, 2001 

Setting Specialty Code Specialty Description Number Percent**

HOPD 10 Gastroenterology 28,879 45.6

2 General surgery 7,385 11.7

11 Internal medicine 4,828 7.6

70 Multispecialty clinic or group practice 2,382 3.8

28 Colorectal surgery 2,121 3.3

ASC 10 Gastroenterology 16,879 71.8

11 Internal medicine 1,507 6.4

2 General surgery 984 4.2

70 Multispecialty clinic or group practice 605 2.6

28 Colorectal surgery 557 2.4

Office 10 Gastroenterology 2,693 67.1

11 Internal medicine 608 15.1

28 Colorectal surgery 199 5.0

2 General surgery 197 4.9

8 Family practice 156 3.9

Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

**Numbers in this column represent percentages of all procedures performed in the indicated

setting. The percentages do not total 100 percent because they represent only the top five

associated with the procedure.

*Specialties were derived from the claims for professional services 

Patient Characteristics 

Looking at all colonoscopies combined, the average risk score for those 

performed in the HOPD (1.08) is higher than those in an office (1.04) or an ASC (1.00) 

(Table 6.5). In the three ambulatory settings combined, the average HCC risk scores 

are similar for the patients having non-RBC and RBC colonoscopies (1.05 and 1.06, 

respectively). This pattern of similar risk scores for RBC and non-RBC colonoscopies 

also holds true for the HOPD setting. However, for colonoscopies performed in the 

ASC and office, the average risk score is slightly higher for the RBC colonoscopies than 

the non-RBC. 
61 

In all three ambulatory sites, the two diagnoses coded most frequently on the 

facility claim are diverticulosis of colon (ICD-9-CM 562.10) and benign neoplasm of 

colon (ICD-9-CM 211.3)25 (Table 6.6). Diverticulosis was coded much more frequently 

on HOPD claims (55 percent) than on ASC claims (33 percent) or office claims (35 

percent). Other common gastrointestinal diagnoses are internal hemorrhoids, colonic 

polyps, and rectal and anal hemorrhage. One co-morbid diagnosis, hypertension (ICD9-CM 401.9), was coded much more frequently on HOPD facility claims (16 percent) 

than on ASC or office claims (less than 1 percent of each). 

The prevalence rates of 12 characteristics that might increase the risk of an 

adverse outcome (i.e., risk factors) among patients having a colonoscopy are shown in 

Table 6.7.26 Each characteristic was identified using all claims for care received by the 

patient in any inpatient or outpatient setting during the months and days of 2001 

preceding the date of the colonoscopy. The prevalence rates are higher among 

patients having the colonoscopy in an HOPD than in an ASC for all 12 risk factors. 

Although based on extremely small numbers, the prevalence rates of several risk 

factors are higher among the patients having colonoscopy in the office than in the 

HOPD. 

 25 The diagnoses for the office setting are derived from the professional, rather than the facility, claim.

26 As mentioned in the Methods section, the cataract surgery panel rated these characteristics with a median of 4 

or higher on a 1-to-9 risk scale, with 9 being high risk.
62 

Table 6.5 Average Risk Scores for Beneficiaries With Colonoscopies (BETOS P8D) By Ambulatory 

Setting, Medicare Fee-for-Service, 2001 

HCPCS Category HOPD ASC Office All Sites

All Colonoscopy 1.08 1.00 1.04 1.06

Non-RBC colonoscopy* 1.08 0.98 1.03 1.05

RBC colonoscopy** 1.08 1.01 1.05 1.06

*Non-RBC colonoscopy includes HCPCS 44388, 45378, and G0105.

**RBC colonoscopy includes HCPCS 44389, 44391, 44392, 

44393, 44394, 45379, 45380, 45382, 45383, 45384, 45385, and 45387.

Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

Table 6.6 Top Ten Diagnoses on Facility Claim for Colonoscopy (BETOS P8D) By Ambulatory 

Setting, Medicare Fee-for-Service System, 2001

ICD-9 Code ICD-9 Code Description

N %** N %** N %** N %**

562.1 Diverticulosis of colon 34,589 54.6 7,703 32.8 1,404 35.0 43,692 48.1

211.3 Benign neoplasm colon 24,696 39.0 9,738 41.4 1,564 39.0 35,995 39.6

455 Internal hemorrhoids without mention of 

complications

17,410 27.5 2,082 8.9 282 7.0 19,773 21.8

V12.72 Colonic polyps 8,080 12.8 2,394 10.2 296 7.4 10,769 11.8

401.9 Essential hypertension, unspecified 10,542 16.6 71 0.3 26 0.6 10,639 11.7

V16.0 Family HX-GI malignancy 5,114 8.1 915 3.9 163 4.1 6,192 6.8

569.3 Rectal & anal hemorrhage 3,350 5.3 1,095 4.7 439 10.9 4,883 5.4

V10.05 HX of colonic malignancy 4,015 6.3 715 3.0 94 2.3 4,824 5.3

578.1 Blood in stool 2,549 4.0 1,391 5.9 259 6.5 4,198 4.6

211.4 Benign neoplasm rectum and anal canal 3,343 5.3 672 2.9 135 3.4 4,150 4.6

*Diagnoses for physician office procedures was derived from professional claims.

percentages might exceed 100 percent because multiple diagnoses can be coded on a single claim.

Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

**Numbers in this column represent percentages of all procedures performed in the indicated setting. The sum of the 

HOPD ASC Office All Sites 
63 

Table 6.7 Selected Risk Factors of Beneficiaries With Colonoscopy (BETOS P8D) By Ambulatory 

Setting, Medicare Fee-for Service System, 2001 

Indicator* Characteristic

N Rate** N Rate** N Rate** N Rate**

N Cardiomyopathy/heart

failure/pulmonary edema with

hospitalization or emergency

department visit within past one year

2,507 39.6 577 24.6 239 59.5 3,323 36.6

BF Melena 1,560 24.6 276 11.7 230 57.3 2,066 22.7

U Aortic stenosis 608 9.6 124 5.3 119 29.6 851 9.4

P History of bleeding disorder 505 8 124 5.3 48 12 677 7.4

AG Persistent severe sinus bradycardia

or sick sinus tachycardia-bradycardia

syndrome

374 5.9 76 3.2 56 13.9 506 5.6

X Malignant hypertension 281 4.4 53 2.3 113 28.1 447 4.9

AC Paroxysmal Ventricular Tachycardia 217 3.4 40 1.7 21 5.2 278 3.1

Y Primary pulmonary hypertension 81 1.3 15 0.6 8 2 104 1.1

AD Patient with Automatic Implanted

Cardioverter Defibrillator (AICD)

83 1.3 12 0.5 2 0.5 97 1.1

F Recent myocardial infarction (> 7

days but fewer than 30 days)

46 0.7 8 0.3 6 1.5 60 0.7

O Orthopnea 29 0.5 4 0.2 6 1.5 39 0.4

E Myocardial infarction within past 7

days

23 0.4 3 0.1 1 0.2 27 0.3

**Per 1,000 procedures.

Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

*Letter codes in this column are taken from the rating form for the RAND expert panel. (Refer to Appendix D)

HOPD ASC Office All Sites
64 

Outcomes 

All adverse outcomes following colonoscopy occurred at a very low rate in 

all three ambulatory settings (Table 6.8) with only four with rates above 10 per 

1000 (abdominal pain, chest pain, dyspnea, and hemorrhage). For 10 of 18 

outcomes, the rates were highest in the office setting, including chest pain, which 

the panel agreed was preventable. For four outcomes, the rates were highest in 

the ASC and for another four, in the HOPD. The rate of perforation, which the 

panel rated as severe (but did not agree on preventability) was highest among 

ASC patients for all colonoscopies, as well as for the subcategories of RBC and 

non-RBC colonoscopies. 

Table 6.8 Selected Outcomes Occurring Within 30 Days Following Colonoscopy (BETOS 

P8D) By Ambulatory Setting, Medicare Fee-for-Service System, 2001

Outcome

N* Rate** N* Rate** N* Rate** N* Rate**

Abdominal pain 2,694 42.5 720 30.6 264 65.8 3,678 40.5

Hemorrhage 1,306 20.6 419 17.8 148 36.9 1,873 20.6

Chest pain 1,076 17.0 163 6.9 107 26.7 1,346 14.8

Dyspnea 754 11.9 93 4.0 69 17.2 916 10.1

Small bowel obstruction 371 5.9 125 5.3 32 8.0 528 5.8

Arrhythmia 185 2.9 41 1.7 27 6.7 253 2.8

Vasovagal reactions 173 2.7 43 1.8 16 4.0 232 2.6

Sepsis and other infections 115 1.8 36 1.5 3 0.7 154 1.7

Abdominal distention 118 1.9 23 1.0 10 2.5 151 1.7

Other complications*** 85 1.3 28 1.2 3 0.7 116 1.3

Hypotension 78 1.2 22 0.9 6 1.5 106 1.2

Perforation 41 0.6 30 1.3 2 0.5 73 0.8

Splenic rupture 30 0.5 4 0.2 1 0.2 35 0.4

Altered mental status 23 0.4 10 0.4 1 0.2 34 0.4

Endocarditis 6 0.1 3 0.1 1 0.2 10 0.1

Hypoxia 2 0.0 2 0.1 0 0.0 4 0.0

Hypertension 1 0.0 1 0.0 0 0.0 2 0.0

Death within 1 week 1 0.0 0 0.0 0 0.0 1 0.0

*Numbers in this column represent the number of outcomes.

**Per 1,000 procedures.

***Other compliations are diagnosis codes 998.89 (Other specified complications of procedures,

not elsewhere classified), and 669.4 (Postoperative complication NOS).

Source: RAND analysis of the 5 percent Standard Analytic Files of Medicare claims, 2001.

HOPD ASC Office All Sites
65 

SUMMARY OF FINDINGS 

Compared to physician offices, a relatively higher proportion of colonoscopies 

performed in HOPDs and ASCs involve some lesion removal, biopsy, or control of 

bleeding. On the issue of patient characteristics, the panel did not reach agreement on 

the appropriateness physician offices as the site of care for patients with moderate risk. 

Of the patient characteristics that might increase risk, the prevalence rates are higher 

among patients having the colonoscopy in an HOPD than in an ASC. Although based 

on extremely small numbers, the prevalence rates of several risk factors are higher 

among the patients having colonoscopy in the office than in the HOPD. Looking at all 

colonoscopies combined, the average risk score for those performed in the HOPD 

(1.08) is higher than those in an office (1.04) or an ASC (1.00). All adverse outcomes 

following colonoscopy occurred at a very low rate in all three ambulatory settings with 

only four with rates above 10 per 1000 (abdominal pain, chest pain, shortness of breath, 

and hemorrhage). 

67 

7. SUMMARY OF FINDINGS AND DISCUSSION 

The analyses described in this report were intended to identify measures that 

could be used to analyze how the nature of a procedure, the patient characteristics, and 

outcomes vary by the setting in which the procedure is provided and to investigate the 

feasibility of using administrative data to measure differences in procedures across 

ambulatory settings. While the study findings indicate that such analyses are feasible, a 

number of issues should be more fully developed before the results are used to draw 

conclusions regarding differences in quality of care or the appropriateness of site-ofservice payment differentials across ambulatory settings. 

In this section, we first summarize our findings for the selected study procedures 

and then discuss general issues that emerged from the expert panels and our empirical 

evaluation. 

SUMMARY OF FINDINGS FOR STUDY PROCEDURES 

MRI of the brain. On the issue of patient characteristics, the panel ratings and 

discussion indicated that MRIs are low risk procedures that can be safely performed in 

the different ambulatory settings. The two conditions that might pose risk- acute 

myocardial infarction (AMI) within the past seven days and automatic implantable 

cardioverter defibrillator (AICD) implants - were thought to occur very infrequently and 

this was confirmed by the empirical evidence. The expert panel discussed the issue of 

generalizability briefly and indicated that it is likely that similar results would be obtained 

from panels discussing other MRI and magnetic resonance angiography procedures, 

with and without contrast materials. 

The empirical data indicated that patients receiving MRI with contrast have 

higher average HCC risk scores than patients receiving MRI without contrast, 

suggesting that they are more medically complex patients. However, after controlling for 

use of contrast media, the pattern of HCC risk scores across the sites is inconsistent. 

The data indicate that a higher proportion of MRIs with contrast are performed in 

HOPDs than in community settings. Both general medical outcomes and procedure-
68 

specific outcomes occurred at a low rate in all three ambulatory settings following MRI, 

but differences across the sites are measurable. For all MRIs (with and without 

contrast), the rates for most outcomes were highest in the office setting. The HOPD 

rates were slightly lower than rates in the office and the rates for IDTFs were 

considerably lower. 

Cataract Surgery. About 97 percent of procedures within this BETOS category 

were for a single HCPCS code. Detecting differences in the procedure across settings is 

problematic because of billing requirements for anesthesia time and materials and 

bundling of intraocular lenses into the facility payment. On the issue of patient 

characteristics, the panel ratings and discussion indicated that these are low risk 

procedures that can be safely performed in either an HOPD or ASC. Nevertheless, 

there are differences in the patient characteristics. The average HCC risk score is 

higher among patients having cataract surgery in an HOPD (1.21) than an ASC (1.14) 

and the prevalence rates are consistently higher for all 17 risk factors among patients 

having the cataract surgery in an HOPD than in an ASC. Adverse outcomes occurred at 

a low rate following cataract surgery. The analyses found few cataract procedures were 

performed in physician offices, but the findings for these procedures suggest that further 

investigation might be warranted. It is difficult to assess how likely these patterns would 

be to persist in other minor ophthalmologic and non-ophthalmologic surgical 

procedures. 

Colonoscopy. Compared to physician offices, a higher proportion of procedures 

performed in HOPDs and ASCs involve some lesion removal, biopsy, or control of 

bleeding. On the issue of patient characteristics, the panel did not reach agreement on 

the appropriateness of physician offices as the site of care for several types of 

colonoscopies. Of the patient characteristics that might increase risk, the prevalence 

rates are higher among patients having the colonoscopy in an HOPD than in an ASC. 

Although based on extremely small numbers, the prevalence rates of several risk 

factors are higher among the patients having colonoscopy in the office than in the 

HOPD. Looking at all colonoscopies combined, the average HCC risk score for those 

performed in the HOPD (1.08) is higher than those in an office (1.04) or an ASC (1.00). 

All adverse outcomes following colonoscopy occurred at a very low rate in all three 
69 

ambulatory settings with only four with rates above 10 per 1000 (abdominal pain, chest 

pain, shortness of breath, and hemorrhage). The panel and RAND staff thought these 

risk patterns would likely be similar for other elective endoscopic procedures. 

DISCUSSION 

Expert Panels 

The expert panels were a critical component of the study since the panel ratings 

targeted the measures that would be most appropriate for investigating variations in the 

study procedures across ambulatory settings. Several crosscutting themes emerged 

from the panel discussions and ratings that merit highlighting: 

• The three study procedures were low-risk procedures that for most patients are 

appropriately performed across different ambulatory sites as long as the site has 

properly trained staff and appropriate equipment. The panelists identified only a 

few instances (e.g., MRI with anesthesia or high contrast media) where the 

panelists agreed it might be inappropriate to furnish the service in non-hospital 

settings. The colonoscopy panel was divided on the appropriateness of 

performing more complex procedures on higher risk patients in office settings. 

• While Medicare has different health and safety standards for hospitals, ASCs, 

and IDTFs, it is not clear whether these have implications for how care is 

delivered across these settings. An off-campus hospital outpatient surgery center 

may be more like a freestanding ASC than the hospital-affiliated ASC that is colocated on the hospital’s main campus. Differences in the typical care 

processes, physician specialties and equipment in an IDTF compared to a 

physician office are not well understood. State licensure laws and accreditation 

may be important factors in understanding the differences. For example, several 

panelists at the colonoscopy panel argued that some state licensure laws require 

that a physician office performing colonoscopies “look like an ASC” and should 
70 

not be rated based on a typical physician office. The division among the panel 

members over the appropriateness of furnishing particular colonoscopies in 

physician offices may be indicative of different perceptions of the structural 

characteristics of physician offices where colonoscopies are performed. 

• Risk was rated higher for procedures that require general anesthesia and high 

dose contrast media. A MRI panelist noted that the Joint Commission on 

Accreditation of Healthcare Organizations (JCAHO) had stringent monitoring 

requirements for the administration of contrast media that might have both cost 

and quality implications relative to non-JCAHO accredited facilities. 

• We asked during the panel meetings whether there were particular patient 

subgroups that might require additional resources. Each panel provided specific 

examples but no ratings were solicited on the examples. For example, the MRI 

panel indicated a patient with claustrophobia was more time-consuming and may 

require sedatives. Only one or two examples were identified in each panel 

meeting and the three panels did not identify the same general health conditions. 

• The generalizability of the findings to other procedures varied. Panelists felt that 

the risk patterns elucidated for MRI of the head, neck and brain would likely apply 

to other MRI and MRA procedures, even though they did not formally evaluate 

this. Similarly the patterns observed for colonoscopy would likely apply to other 

elective endoscopic procedures, though the underlying patients characteristics 

would probably have very different distributions. The cataract panelists, in 

contrast, found it difficult to ascertain how other minor ophthalmologic procedures 

would compare to their findings. 

Empirical Evaluation 

The second component of this task was to apply the set of clinically based 

measures to the claims data for a 5 percent sample of Medicare beneficiaries. Using 

claims data to examine potential differences in quality and processes of care across 
71 

ambulatory settings has several advantages. Medicare claims data are routinely 

collected and relatively inexpensive to analyze. They are available relatively quickly – 

there is a lag of seven months between the end of a calendar year and the release of 

Standard Analytic Files (SAF) of Medicare claims from CMS. Thus, measures based on 

claims data can be calculated in a timely fashion. The availability of claims data on an 

ongoing basis allows periodic evaluation crucial to identifying emerging trends and 

evaluating the impact of policy. However, outcomes can be difficult to measure using 

administrative data because clinical detail is lacking and data elements not directly 

related to payment might be unreliable. 

Using administrative data to examine the study questions involved complex 

matching of provider and professional claims that had different formats, variables, and 

reporting requirements. The variables from claims data used in our analyses include 

dates of service, procedure codes and modifiers, and diagnostic codes. For an earlier 

task in this project that involved estimating Medicare volume and spending for specific 

procedures by site of service, Social and Scientific Systems, Inc. created analytic files 

that matched facility and professional service claims. This matching was done because 

the place of service coding on professional claims is often inaccurate. In the current 

task, considerable resources were expended to link the facility claim for a given index 

procedure with the associated claims for professional services. For the non-anesthesia 

professional claims, we were interested in determining whether there were differences 

in the diagnostic and procedure coding on the facility claim and the modifier descriptions 

of the professional services. We found that these professional claims provided little 

additional information relative to what is provided without the matching process and that 

the matching may be unnecessary to examine most issues related to patient 

characteristics and quality of care within a BETOS category. It becomes more 

important, however, if particular procedures are at issue, since as discussed below, we 

found differences in the procedure coding on the facility and professional claims. 

Analysis of the anesthesia services presented a unique set of challenges. First, 

the match rate to facility claims is lower because unique HCPCS and BETOS codes for 

anesthesia preclude matching on these variables in addition to date of service. Second, 

actual time units, which potentially could be used to measure differences in the length of 
72 

procedures, are not available on the SAF; instead, time intervals (MTUS) are reported. 

The MTUS are either in 15-minute or 30-minute intervals, depending on whether the 

anesthesia is personally administered or medical direction of a CRNA is involved, 

whether there are concurrent procedures, and if monitored anesthesia care is provided. 

Teasing useful information from the MTUS would not be a trivial task, particularly since 

the reasons why procedures are longer in one setting or another would still need to be 

determined. For example, longer procedure times could be indicative of differences in 

patient characteristics or could indicate differences in productivity. 

Although the rate of missing information on date of service is low because it is 

required for payment of a claim, the date of service on the claim might be different from 

the date the procedure was actually performed. In addition, the claim from and through 

dates and the line item date of service might be different, necessitating a decision 

regarding which date is more accurate. When matching facility and professional claims 

for the same procedure, we needed to employ an algorithm for the dates of services to 

allow for a difference of one or more days. Otherwise, procedures might be doublecounted due to unmatched records for the same procedure. These situations 

emphasize that caution must be exercised in identifying and interpreting dates of 

services on claims. 

Two general issues of concern regarding procedure codes are (1) the use of 

multiple codes for the same or related procedures with the same date on the same 

claim, and (2) differences in procedure codes between the facility and professional 

claims. Related to the first issue, as reported earlier in the results sections, we found 

that many claims have from two to five HCPCS procedure codes within the same 

BETOS category coded with the same date. In fact, the multiple HCPCS codes were 

identical on many of the records having multiple procedures in the same BETOS. 

Without further examination, it is difficult to know for certain whether this represents 

different components of the same procedure, a coding error, or repeat procedures. 

Since the multiple procedures occur most often for services furnished in the physician 

office setting, it is likely most are different components of the same service. For 

example, multiple procedure code line items may have been billed with the appropriate 

modifiers on the same date of service when a physician other than the surgeon 
73 

performing the cataract procedure furnished pre- and/or post-operative care. Related to 

the second issue, in the process of matching the facility and professional claims, we 

were able to match a much higher proportion of records using the beneficiary ID, date of 

service, and the BETOS code rather than using beneficiary ID, date of service, and the 

HCPCS code. This indicates that the HCPCS procedure code on the facility claim 

frequently differs from the HCPCS code on the professional claim and could complicate 

procedure-specific analyses. 

 There are also concerns about using claims data for condition-specific analyses 

because identifying clinical subgroups of patients with ICD-9-CM codes might be 

problematic. These concerns fall into two categories: 1) the ICD-9-CM diagnostic 

nomenclature, and 2) the use of ICD-9-CM diagnostic codes (Iezzoni, 1990). The ICD9-CM nomenclature contains many ambiguities. Codes may be vague (e.g., heart 

failure, unspecified) and contain symptomatic as well as etiologic codes (e.g., fatigue). 

In addition, the nomenclature provides only limited indicators of the severity of a 

condition. This makes identifying specific clinical outcomes following a procedure 

problematic. For example, the colonoscopy panel noted that some complications can 

range from minor to severe. Concerned with the potential under-reporting of 

complications, the panel rated complications with the understanding that only those that 

are severe are likely to be found in the administrative data. 

The way hospitals and providers use the codes might also exacerbate some of 

the problems inherent in the nomenclature. For example, while inpatient claims data 

usually contain multiple diagnoses for each admission, most outpatient claims contain at 

most a few diagnostic codes. Also, generating hospital payment based on the Medicare 

DRG system, which is based on the ICD-9-CM codes, has introduced a potential 

pecuniary bias into coding practices known as "DRG creep” (Simborg, 1981). Studies 

to validate ICD-9-CM with chart-based reviews have uncovered substantial inaccuracies 

and unexplained geographic variation (IOM, 1980). The degree of inaccuracy, however, 

depends greatly on the condition and algorithm used to detect the condition (Quam et 

al., 1993). 

Attributing outcomes to particular procedures is often problematic. In particular, 

both the cataract and MRI panels expressed concern that conditions following the 
74 

procedure may be more indicative of ineffective or poor pre-or post-operative care than 

being complications related to the actual procedure. The cataract panel suggested 

limiting the more general health outcomes to those occurring within 7 days compared to 

a 30-day window for eye-specific complications. Using bleeding as an example, the 

colonoscopy panel also cautioned that it might be difficult to distinguish a potential 

complication of the colonoscopy from the symptoms that created the need for the 

procedure. 

In these preliminary analyses, we controlled for major procedure differences that 

might affect outcomes by separately examining complication rates for MRI with and 

without contrast media and colonoscopy with and without “RBC.” (Cataract surgeries 

were dominated by one procedure code and therefore were not categorized by 

procedure characteristics). However, we did not control for differences in patient 

characteristics across settings that might affect outcomes. In this regard, the cataract 

panel suggested it would be important to look at rates for cystoid macular edema 

separately for diabetic and non-diabetic patients since diabetes make the condition less 

preventable. For congestive heart failure, the panelists suggested that the analysis 

should look for signs of new or worsening congestive heart failure. These are the types 

of refinements that would need to be made before any conclusions could be made 

concerning differences in quality of care across ambulatory settings. 

One study question was whether there are differences in the nature of the 

procedure in different settings. Other than differences that are accounted for by the 

HCPCS codes and modifiers, we found our ability to address this issue through the 

administrative data was limited. As noted above, we were not able to use the 

anesthesia claims to assess whether there are differences in the length of surgical 

procedures and, because of match rates, results concerning type of anesthesia are 

problematic. For those claims that we were able to match, we generated some 

interesting information regarding how professional anesthesia services are furnished in 

ASCs and HOPDs; however, the study focus is on facility, not professional services. 

Multiple MRI sequences also increase costs but are also not fully captured in 

comparative data. 
75 

Opportunity to examine product differences was also affected by the different 

payment rules for ambulatory services. For example, we were unable to compare 

anesthetics across the settings because the anesthetic is bundled into the facility 

payment to both ASCs and HOPDs. Some information is available in the claims 

regarding high dose contrast media provided in physician offices and IDTFs; however, 

payment is bundled into the APC payment and the type of contrast media may not be 

reliably reported on HOPD claims data.27 One distinction between HOPDs and the 

other ambulatory settings is that resident training, which may increase procedure time, 

takes place almost exclusively in HOPD settings. 

A related study question was whether administrative data could be used to 

determine if there are differences in the patient characteristics across the three settings 

that might affect the resources required to perform the procedure. Enrollment data 

provide information is available on patient demographics (age, sex, race) and factors 

that might affect the medical complexity of a patient (Medicaid status, entitlement based 

on disability or end-stage renal disease). The claims history also provides a mechanism 

to identify patients with particular conditions requiring medical care subject to the 

limitations discussed above regarding the use of ICD-9-CM codes. The claims history 

can also be used to assign patients to HCC risk categories that can be used to 

summarize the patient’s medical complexity based on predicted needs. The underlying 

assumption is that performing a diagnostic or surgical procedure on a medically 

complex patient or patient with a particular condition such as dementia may require 

more resources; however, this is an empirical question that cannot be answered directly 

with administrative data. Since our literature review did not find information on this 

issue, we asked during the panel meetings whether there were particular patient 

subgroups that might require additional resources. Each panel provided specific 

examples but no ratings were solicited on the examples. For example, the MRI panel 

indicated a patient with claustrophobia was more time-consuming and may require 

 27 It is likely that most procedures involving high dose contrast media are reported under CPT codes 

70543, 70546, 70549, and 70553 (which report MRIs and MRAs of the head, neck or brain involving without 

contrast material, followed by with contrast material(s) and further sequences). However, it cannot be assumed 

that these codes are used exclusively for high dose contrast media nor that high dose contrast media is used 

only after no contrast materials and lower dose materials are used.
76 

sedatives. Patients with dementia and those with monocular vision were identified by 

the colonoscopy and cataract panels, respectively, as requiring more time. In retrospect, 

it is not clear whether the additional time for monocular patients related to facility 

services or professional services, or both. 

The overall limitations of claims data and of specific variables used in our 

analysis do not mean that claims data should not be used for clinically-based measures, 

though confirmation with more clinically detailed methods such as chart review would be 

desirable. The expert panel ratings and our preliminary analyses for the three 

procedures suggest that with further refinement the administrative data can be used to 

reach a number of policy-relevant conclusions that have implications not only for the 

study procedures but also for other procedures with similar risk. 
77 

APPENDIX A. HCPCS (CPT) CODES FOR THREE STUDY PROCEDURES 

BETOS I2C: ADVANCED IMAGING—MRI: HEAD, NECK, AND BRAIN 

CPT Code CPT Description 

70541 Magnetic resonance angiography, head and/or neck, with or without 

contrast material(s). 

70542 MR (e.g., proton) imaging, orbit, face, and neck; with contrast material 

70543 MR (e.g., proton) imaging, orbit, face, and neck; without contrast material, 

followed by contrast material(s) and further sequences. 

70544 MR angiography, head; without contrast material(s) 

70545 MR angiography, head; with contrast material(s) 

70546 MR angiography, head; without contrast material, followed by contrast 

material(s) and further sequences. 

70547 MR angiography, neck; without contrast material(s) 

70548 MR angiography, neck; with contrast material(s) 

70549 MR angiography, neck; without contrast material, followed by contrast 

material(s) and further sequences. 

70551 Magnetic resonance (e.g., proton) imaging, brain (including brain stem); 

without contrast material 

70552 Magnetic resonance (e.g., proton) imaging, brain (including brain stem); 

with contrast material(s). 

70553 Magnetic resonance (e.g., proton) imaging, brain (including brain stem); 

without contrast material, followed by contrast material(s) and further 

sequences. 
78 

BETOS P4B: EYE PROCEDURE—CATARACT REMOVAL/LENS INSERTION 

CPT 

Code CPT Description 

66820* Discission of secondary membranous cataract (opacified posterior lens 

capsule and/or anterior hyaloid); stab incision technique (Ziegler or Wheeler 

knife). 

66830 Removal of secondary membranous cataract (opacified posterior lens 

capsule and/or anterior hyaloid) with corneo-scleral section, with or without 

iridectomy (iridocapsulotomy, iridocapsulectomy). 

66840 Removal of lens material; aspiration technique, one or more stages. 

66850 Removal of lens material; phacofragmentation technique (mechanical or 

ultrasonic) (e.g., phacoemulsification), with aspiration. 

66852 Removal of lens material; pars plana approach, with or without vitrectomy. 

66920 Removal of lens material; intracapsular. 

66930 Removal of lens material; intracapsular, for dislocated lens. 

66940 Removal of lens material; extracapsular (other than 66840, 66850, 66852). 

66982 Extracapsular cataract removal with insertion of intraocular lens prosthesis 

(one stage procedure), manual or mechanical technique, (eg, irrigation and 

aspiration or phacoemulsification), complex, requiring devices or techniques 

not generally used in routine cataract surgery (eg, iris expansion device, 

suture support for intraocular lens, or primary posterior capsulorrhexis) or 

performed on patients in the amblyogenic developmental stage 

66983 Intracapsular cataract extraction with insertion of intraocular lens prosthesis 

(one stage procedure). 

66984 Extracapsular cataract removal with insertion of intraocular lens prosthesis 

(one stage procedure), manual or mechanical technique (eg, irrigation and 

aspiration or phacoemulsification). 

66985 Insertion of intraocular lens prosthesis (secondary implant), not associated 

with concurrent cataract removal. 

66986 Exchange of intraocular lens. 

 *The CPT code 66820 is in BETOS category P4E (Eye procedure - other). 
79 

BETOS P8D: ENDOSCOPY—COLONOSCOPY 

CPT 

Code CPT Description 

44388 Colonoscopy through stoma; diagnostic, with or without collection 

of specimen(s) by brushing or washing (separate procedure). 

44389 Colonoscopy through stoma; with biopsy, single or multiple. 

44390 Colonoscopy for foreign body 

44391 Colonoscopy through stoma; with control of bleeding, any method. 

44392 Colonoscopy through stoma; with removal of tumor(s), polyp(s), or 

other lesion(s) by hot biopsy forceps or bipolar cautery. 

44393 Colonoscopy through stoma; with ablation of tumor(s), polyp(s), or 

other lesion(s) not amenable to removal by hot biopsy forceps, 

bipolar cautery or snare technique. 

44394 Colonoscopy through stoma; with removal of tumor(s), polyp(s), or 

other lesion(s) by snare technique. 

44397 Colonoscopy w/stent 

45355 Surgical colonoscopy 

45378 Colonoscopy, flexible, proximal to splenic flexure; diagnostic, with 

or without collection of specimen(s) by brushing or washing, with or 

without colon decompression (separate procedure). 

45379 Colonoscopy, flexible, proximal to splenic flexure; with removal of 

foreign body. 

45380 Colonoscopy, flexible, proximal to splenic flexure; with biopsy, 

single or multiple. 

45382 Colonoscopy, flexible, proximal to splenic flexure; with control of 

bleeding, any method. 

45383 Colonoscopy, flexible, proximal to splenic flexure; with ablation of 

tumor(s), polyp(s), or other lesion(s) not amenable to removal by 

hot biopsy forceps, bipolar cautery or snare technique. 

45384 Colonoscopy, flexible, proximal to splenic flexure; with removal of 

tumor(s), polyp(s), or other lesion(s) by hot biopsy forceps or 

bipolar cautery. 

45385 Colonoscopy, flexible, proximal to splenic flexure; with removal of 

tumor(s), polyp(s), or other lesion(s) by snare technique. 

45387 Colonoscopy, flexible, proximal to splenic flexure; with 

transendoscopic stent placement (includes predilation) 

G0105* Colorectal screen; high risk individual 

 *Level II HCPCS code. 

81 

APPENDIX B. EXPERT PANEL FOR MRI OF BRAIN, HEAD AND NECK 

February 12, 2004 

Dr. Yoshimi Anzai, MD 

Associate Professor, Department of 

Radiology 

University of Washington Medical Center 

1959 N.E. Pacific Street, Box 357115 

Seattle, WA 98195-7115 

Dr. Michael Brant-Zawadzki 

Hoag Memorial Hosp.

Radiology Dept., One Hoag Dr., Box 6100 

Newport Beach, CA 92658-6100 

 Dr. Carl Ellenberger, Jr, MD 

GSH Imaging Center 

Box 70 

320 Oak Street 

Lebanon, PA 17042 

Dr. Geoffrey Hartwig 

 415 South 28th Avenue 

Hattiesburg, MS 39402 

Dr. Vincent P. Mathews 

Northwest Radiology Network 

5756 W. 71st St. 

Indianapolis, IN 46278 

Dr. Robert A. Murray, MD 

Rockford Memorial Hosp. 

Radiology Dept., 2400 N. Rockton Ave. 

Rockford, IL 61103 

[completed task 1 and 2, but not panel 

discussion] 

Dr. C. Douglas Phillips 

Univ. Virginia Health Syst. 

Dept. of Radiology, Box 800170, Lee St. 

Charlottesville, VA 22908 

Facilitator: Dr. Steven Asch, RAND 

Dr. Victoria Rand 

San Francisco, CA 94131 

Dr. Gerald Smetana, MD 

Division of General Medicine and Primary 

Care 

Beth Israel Deaconess Medical Center 

Boston 

Shapiro-621 

330 Brookline Avenue 

Boston, MA 02215 

[participated in both cataract and MRI 

panels] 
82 

MRI RATING FORMS AND EXPERT PANEL PROCESS 

A. Outcomes/complications, round “0” (first-round): preventability and severity. 

Panelist provided ratings prior to the panel discussion and faxed their responses. The 

panelists’ responses were entered into a database. 

B. Outcomes/complications, round “1” (second-round) with rating summary: 

preventability and severity. Some panelists suggested additional outcomes that should 

be included. Others suggested that some of the terms should be altered slightly. 

Panelists received this rating form, which incorporates suggestions from “round 0,” and 

a summary of the scores for each indicator. Panelists completed the rating form again 

during the panel discussion. 

C. Patient characteristics: risk. Panelists provided tentative ratings prior to the panel 

discussion and made final ratings during the teleconference. 

D. Procedure characteristics: appropriateness across outpatient settings. Panelists 

provided tentative ratings prior to the panel discussion and made final ratings during the 

teleconference 
83 

SUMMARY OF MRI EXPERT PANEL RATINGS FOR PATIENT CHARACTERISTIC

IDTF

Patient Characteristics #

Resp

Median Mean

Dev

Agree? <4 4-6 >6 #

Resp

Median Mean

Dev

Agree

?

<4 4-6 >6 #

Resp

Me

A Age > 70 years 1 Y 8 0 0 1 8 0 0 

B

8 0.38 8 0.50 Y 8 

Age > 85 years 8 2 0.63 Y 7 1 0 8 2 0.63 Y 8 0 0 8 

C Stable angina 7 1 0.43 Y 7 0 0 7 1 0.71 Y 6 1 0 7 

D Unstable angina in last 3 

months

7 3 1.00 Y 6 1 0 7 4 1.29 I 3 3 1 7 

E Myocardial infarction within

past 7 days

8 4 1.63 N 3 2 3 8 4.5 1.88 N 2 3 3 8 4

F Recent myocardial

infarction (> 7 days but fewer than 30 days)

8 2.5 1.44 Y 6 2 0 8 3.5 1.88 I 4 3 1 8 3

G Myocardial infarction (>30 

days but fewer than 6 months)

8 2 1.25 6 2 0 8 2.5 1.50 I 6 1 1 8 

H Old myocardial infarction (>

6 months)

8 1 0.63 Y 7 1 0 8 1 0.88 Y 6 2 0 8 

I Chronic obstructive

pulmonary disease with hospitalization oremergency department visit within past one year

8 2 0.50 Y 8 0 0 8 2 0.88 Y 6 2 0 8 

J Asthma with hospitalization

or emergency department visit within past one year

8 2 0.50 Y 8 0 0 8 2 0.88 Y 6 2 0 8 

K Cardiomyopathy/heart 

failure/pulmonary edema with hospitalization or emergency department visit within past one year

8 2.5 0.81 Y 7 1 0 8 3 1.50 Y 4 4 0 8 

L Orthopnea 8 2.5 0.81 Y 7 1 0 8 3 1.13 Y 5 3 0 8 3

HOSPITAL OUTPATIENT DEPT PHYS
84 

IDTF

Patient Characteristics # Resp Median Mean

Dev

Agree? <4 4-6 >6 # Resp Median Mean

Dev

Agree

?

<4 4-6 >6 # Res

M Diabetes mellitus (Type 2),

requiring insulin

8 1 0.38 Y 8 0 0 8 1.5 0.63 Y 8 0 0 8 

N Chronic renal failure,

requiring hemodialysis

8 2 0.25 Y 8 0 0 8 2 0.25 Y 8 0 0 8 

O Chronic renal failure, not

requiring hemodialysis

8 2 0.38 Y 8 0 0 8 2 0.63 Y 8 0 0 8 

P Mobitz Type 2 

Atrioventricular block

8 1.5 1.69 N 6 0 2 8 1.5 2.25 N 6 0 2 8 

Q Anomalous atrioventricular

excitation including:accelerated, accessory, ventricular preexcitation, Wolff-ParkinsonWhite syndrome

8 1.5 1.69 N 6 0 2 8 1.5 2.25 N 6 0 2 8 

R Paroxysmal

SupraventricularTachycardia

8 1 1.13 Y 6 2 0 8 1 1.75 N 6 0 2 8 

S Paroxysmal Ventricular

Tachycardia

8 2 1.75 I 5 2 1 8 2.5 2.38 N 5 1 2 8 

T Patient with Automatic 

Implanted CardioverterDefibrillator (AICD)

8 9 0.88 I 1 0 7 8 9 0.50 Y 0 1 6 8 

U Atrial fibrillation 8 1 0.75 Y 6 2 0 8 1 1.25 Y 6 2 0 8 

V Atrial flutter in past 6 

th

8 1 0.50 Y 8 0 0 8 1 1.00 Y 6 2 0 8 

W Persistent severe sinus 

bradycardia or sick sinus tachycardia-bradycardia syndrome

8 1 0.75 Y 7 1 0 8 1.5 1.38 I 6 1 1 8 

X Seizure disorder 8 1 0.50 Y 8 0 0 8 1 1.00 Y 6 2 0 8 

Y Dementia 8 1 0.25 Y 8 0 0 8 1 0.38 Y 8 0 0 8 Z Stroke within past 6 months 8 1 0.25 Y 8 0 0 8 1 0.38 Y 8 0 0 8 

HOSPITAL OUTPATIENT DEPT P
85 

IDTF

Patient Characteristics

# Resp Median Mean 

Dev

Agree? <4 4-6 >6 #

Resp

Median Mean 

Dev

Agree

?

<4 4-6 >6 #

Resp

Median 

HOSPITAL OUTPATIENT DEPT PHYSICIAN 

AA Barbiturate,

chlordiazepoxide, diazepam,glutethimide, meprobamate,or methaqualone 

d d

8 2 0.75 Y 7 1 0 8 2 1.38 I 7 0 1 8 2 

AB Opioid type dependence 8 1.5 0.81 Y 7 1 0 8 1.5 1.25 I 7 0 1 8 1.5 

AC Alcohol abuse 8 1.5 0.44 Y 8 0 0 8 1.5 0.63 Y 8 0 0 8 1.5 

AD Anxiety 8 1 0.50 Y 8 0 0 8 1.5 1.25 I 7 0 1 8 1.5 

AE Schizophrenic disorder 8 1 0.25 Y 8 0 0 8 1 0.50 Y 8 0 0 8 1 AF History of Claustrophob ia 8 1 0.50 Y 8 0 0 8 1 1.00 I 7 0 1 8 1 AG Personal history of allergy to

anesthetic agent

8 1.5 0.56 Y 8 0 0 8 2 1.50 I 6 1 1 8 2 

AH History of shock due to

anesthesia in which correctsubstance was properlyadministered

8 1.5 0.69 Y 7 1 0 8 2 1.38 I 6 1 1 8 2 

AI Essential, Benign, or DrugRelated Tremor 8 1 0.13 Y 8 0 0 8 1 0.63 Y 7 1 0 8 1 

AJ Abnormal head movements,

Fasciculations, Spasms, orTremor Not OtherwiseSpecified

8 1 0.38 Y 8 0 0 8 1 1.25 I 6 1 1 8 1 

AL Personal allergy to

radiographic dye

8 1 0.38 Y 8 0 0 8 1.5 0.50 Y 8 0 0 8 1.5 

AM History of anaphylactic shock

not otherwise specified ordue to adverse effect of correct medicinal substance properly administered,excluding anaphylacticreaction to serum or adverse

8 1.5 1.19 Y 6 2 0 8 2.5 1.88 I 5 2 1 8 2.5 
86 

IDTF

Patient Characteristics

# Resp Median Mean

Dev

Agree? <4 4-6 >6 #

Resp

Median Mean

Dev

Agree

?

<4 4-6 >6 #

Resp

Median Mean

Dev

HOSPITAL OUTPATIENT DEPT PHYSICIANOFF

AN Cerebral edema 8 2.5 0.81 Y 7 1 0 8 4 1.75 I 4 3 1 8 4.5 1.63 

AO Malignant neoplasm of the 

brain

8 1.5 0.56 Y 8 0 0 8 2 1.13 I 7 0 1 8 2.5 1.25 

AP Malignant neoplasm of the 

eye, excluding carcinoma insitu, eyelid (skin), cartilage,optic nerve, or orbital bone

8 1 0.13 Y 8 0 0 8 1 0.63 Y 7 1 0 8 1 0.75 

AQ Retained (old) MAGNETIC

intraocular foreign body,

8 6 2.00 N 2 2 4 8 6 2.38 N 2 2 4 8 6 2.38 

AR Retained (old) retrobulbar 

foreign body

8 4.5 1.56 N 3 3 2 8 4.5 2.00 N 2 4 2 8 4.5 2.00 

AS Penetration of eyeball with

MAGNETIC foreign body(open wound of eyeball), (notold)

8 6 2.13 N 2 2 4 8 6 2.38 N 2 2 4 8 6 2.38 

AT Penetrating wound of orbit

with foreign body (openwound of ocular adnexa)

8 4.5 1.94 N 3 2 3 8 4.5 2.50 N 3 2 3 8 4.5 2.50 
87 

SUMMARY OF MRI EXPERT PANEL RATINGS FOR PROCEDURE CHARACTERIS

Procedure

# 

Resp

Median Mean

Dev

Agree

?

<4 4-6 >6 #

Resp

Median Mean

Dev

Agree

?

<4 4-6 >6 #

Resp

Median 

A MRI head without dye

8 9 0.00 Y 0 8 6 9 0.00 Y 0 8 8 9 

B MRI head with dye 8 9 0.13 Y 0 8 6 9 0.00 Y 0 8 8 8.5 

C MRI with anesthesia 8 9 0.50 Y 0 8 6 8.5 1.50 Y 0 6 8 7 D High dose contrast 

MRI 8 2 2.13 N 6 2 6 2 2.17 I 6 1 8 1 

# 

Resp

Median Mean

Dev

Agree

?

<4 4-6 >6 #

Resp

Median Mean

Dev

Agree

?

<4 4-6 >6 #

Resp

Median 

A MRI head without dye

8 9 0.00 Y 0 7 7 9 0.00 Y 0 7 7 9 

B MRI head with dye 8 9 0.14 Y 0 7 7 9 0.00 Y 0 7 7 8 

C MRI with anesthesia 8 9 1.00 Y 0 6 7 7 1.14 Y 0 5 7 7 D High dose contrast 

MRI 8 2 2.29 N 5 2 7 2 1.71 I 5 1 7 1 

# 

Resp

Median Mean

Dev

Agree

?

<4 4-6 >6 #

Resp

Median Mean

Dev

Agree

?

<4 4-6 >6 #

Resp

Median 

A MRI head without dye

7 9 0.00 Y 0 7 7 9 0.14 Y 0 7 7 8 

B MRI head with dye 7 9 0.14 Y 0 7 7 9 0.29 Y 0 7 7 7 

C MRI with anesthesia 7 3 2.71 N 4 3 7 2 2.14 I 4 1 7 1 D High dose contrast 

MRI 7 2 2.43 N 5 2 7 1 1.86 I 5 1 7 1 

# 

Resp

Median Mean

Dev

Agree

?

<4 4-6 >6 #

Resp

Median Mean

Dev

Agree

?

<4 4-6 >6 #

Resp

Median 

A MRI head without dye

7 9 0.00 Y 0 7 7 9 0.14 Y 0 7 7 7 

B MRI head with dye 7 9 0.14 Y 0 7 7 9 0.43 Y 0 7 7 6 

C MRI with anesthesia 7 3 2.29 N 4 2 7 1 2.00 N 5 2 7 1 D High dose contrast 

MRI 7 2 2.43 N 5 2 7 1 1.86 I 5 1 7 1 

NORMAL OR VERY LOW RISK LOW-MODERATE RISK MO

HOSPITAL OUTPATIENT DEPARTMENT

HOSPITAL EMERGENCY ROOM

PHYSICIAN OFFICE

INDEPENDENT TREATMENT FACILITY
88 

SUMMARY FOR MRI EXPERT PANEL RATINGS FOR PATIENT OUTCOMES 

Outcomes

# 

Resp

Median Mean 

Dev

Agree

?

<4 4-6 >6 # Resp Median Mean 

Dev

Ag

?

A Altered mental status 7 2 0.71 Y 7 0 0 7 2 1.00 Y B Anaphylaxis/anaphylactoid 

reaction

7 2 1.29 Y 5 2 0 7 8 0.43 Y 

C Bradycardia 7 1 0.57 Y 7 0 0 7 2 0.71 Y 

D Chest pain 7 1 0.29 Y 7 0 0 7 3 1.57 Y E Death 6 5.5 2.00 I 2 3 1 6 9 0.00 Y F Dizziness 5 1 0.80 Y 5 0 0 6 2 0.50 Y G Dyspnea 6 3 0.67 Y 5 1 0 6 4.5 1.50 I 

H Headache 6 1 0.17 Y 6 0 0 4 2 0.00 Y I Hypertension 6 2 0.67 Y 6 0 0 6 3 1.00 Y 

J Hypotension 6 2 1.00 Y 5 1 0 6 4.5 1.50 Y K Ocular injury 6 8 0.67 Y 0 0 6 6 8 1.17 I 

L Paresthesia 7 1 0.71 Y 7 0 0 7 1 0.57 Y M Rash 7 3 1.14 Y 5 2 0 7 2 0.71 Y N Seizure 6 1 0.17 Y 6 0 0 7 5 1.71 I O Syncope 7 1 1.14 Y 5 2 0 7 2 1.86 I 

P Tachycardia 7 2 1.14 Y 6 1 0 7 3 1.29 Y 

Q Vasodilatation 7 1 0.57 Y 6 1 0 7 3 1.00 Y R Vasospasm 7 1 0.86 Y 6 1 0 7 3 1.00 Y 

PREVENTABLE SEVERITY
89 

APPENDIX C. EXPERT PANEL ON CATARACT SURGERY 

February 4, 2004 

Dr. Marc Allan Feldman 

The Cleveland Clinic 

9500 Euclid Avenue 

Mail Code: E31 

Cleveland, OH 44195 

(216) 444-9088 

Dr. Steve Gayer 

10424 SW 17 Manor 

Davie, FL 33324 

[completed task 1 and 2, but not panel 

discussion] 

Dr. Greg Kwasny, MD 

Eye Surgery Associates, S.C. 

2300 N. Mayfair Rd. #1030 

Milwaukee, WI 53226 

Dr. Samuel Masket 

Advanced Vision Care 

2080 Century Park East, #911 

Los Angeles, Ca 90067 

Dr. Stephen Obstbaum 

115 E. 39th Street 

New York, NY 10016 

Dr. Priscilla Perry Arnold 

Springfield, MO 65809 

Dr. Stephen Ross 

1304 15th Street, Suite 400 

Santa Monica, CA 90404 

Dr. Harry Zink, MD 

3519 Friendsville Road 

Wooster, OH 44691 

Facilitator: Dr. Steven Asch, RAND 

Dr. Gerald Smetana, MD 

Division of General Medicine and Primary 

Care 

Beth Israel Deaconess Medical Center 

Boston 

Shapiro-621 

330 Brookline Avenue 

Boston, MA 02215 

[participated in both cataract and MRI 

panels] 
90 

CATARACT RATING FORMS AND EXPERT PANEL PROCESS 

A. Outcomes/complications, round “0” (first-round): preventability and severity. 

Panelist provided ratings prior to the panel discussion and faxed their responses. The 

panelists’ responses were entered into a database. 

B. Outcomes/complications, round “1” (second-round) with rating summary: 

preventability and severity. Some panelists suggested additional outcomes that should 

be included. Others suggested that some of the terms should be altered slightly. 

Panelists received this rating form, which incorporates suggestions from “round 0,” and 

a summary of the scores for each indicator. Panelists completed the rating form again 

during the panel discussion. 

C. Patient characteristics: risk. Panelists completed this rating form during the panel 

discussion. 

D. Procedure characteristics: appropriateness across outpatient settings. Panelists 

briefly discussed procedure characteristics and completed the rating form after the 

panel discussion. 

E. Follow-up email sent to cataract panelists reminding panelists to return comments 

about cataract surgery. Because there was insufficient time to discuss all of the 

procedure characteristics, the panelists were asked to review the procedure 

characteristics and email comments about the procedure characteristics to the project 

team. 

F. Follow-up email sent to cataract panelists summarizing comments received about 

procedure characteristic. A summary of the panelists’ comments about procedure 

characteristics was emailed to all of the panelists. 
91 

SUMMARY OF CATARACT EXPERT PANEL RATINGS FOR PATIENT CHARACTERI

AMBULATORY 

Patient Characteristics #Resp Median Mean Dev Agree? <4 4-6 >6 #Resp Median Mean D

A Age > 70 years 7 2 0.43 Y 7 0 0 6 1.5 0.50 

B Age > 85 years 7 2 0.43 Y 7 0 0 6 2 0.50 C Stable angina 7 3 0.57 Y 520 6 3 0.67 

D Unstable angina in last 3 months 7 7 1.43 I 1 1 5 6 7.5 1.67 

E Myocardial infarction within past 7

days

7 9 0.14 Y 0 0 7 6 9 0.17 

F Recent myocardial infarction (> 7 days 

but fewer than 30 days)

7 8 0.43 Y 0 0 7 6 8 0.50 

G Myocardial infarction (>30 days but

fewer than 6 mos)

7 6 0.86 Y 0 4 3 6 6.5 1.00 

H Old myocardial infarction (> 6 months) 7 3 1.00 Y 4 3 0 6 3.5 1.17 I Dementia 7 4 0.86 Y 3 4 0 6 3 0.83 J Chronic obstructive pulmonary 

disease with

7 3 0.86 Y 5 2 0 6 2.5 1.00 

K Asthma with hospitalization or

emergency department visit withinpast one year

7 3 1.00 Y 5 2 0 6 2.5 1.17 

L Bronchietasis with acute exacerbation 

within past 6 mos

7 2 1.00 Y 5 2 0 6 2 1.17 

M Cirrhosis 7 3 1.00 Y 5 2 0 6 2.5 1.17 N Cardiomyopathy/heart

failure/pulmonary edema withhospitalization or emergencydepartment visit within one past year

7 4 1.14 I 3 3 1 6 5 1.33 

O Orthopnea 7 3 0.71 Y 4 3 0 6 3.5 1.00 P History of bleeding disorder 7 3 0.71 Y 5 2 0 6 3 0.83 

Q History of adverse effect from

anticoagulation in past 3 months

7 3 0.86 Y 5 2 0 6 2.5 1.00 

R Diabetes mellitus (Type 2), requiring

insulin

7 3 0.43 Y 6 1 0 6 3 0.50 

HOSPITAL OUTPATIENT DEPT
92 

AMBULATORY SURGE

Patient Characterisitcs #Resp Median Mean Dev Agree? <4 4-6 >6 #Resp Median Mean Dev Ag

HOSPITAL OUTPATIENT DEPT

S Diabetes mellitus (Type 2), not

requiring insulin

7 2 0.43 Y 7 0 0 6 2 0.50 Y 

T Chronic renal failure, requiring

hemodialysis

6 3 1.33 Y 4 2 0 5 3 1.60 Y 

U Chronic renal failure, not requiring

hemodialysis

6 2.5 0.75 Y 5 1 0 5 2 0.80 Y 

V Aortic stenosis 6 3 1.17 Y 4 2 0 5 3 1.40 Y 

W Sleep Apnea 6 3 1.00 Y 4 2 0 5 3 1.20 Y X Thyrotoxicosis within past 6 months 6 2.5 1.25 Y 4 2 0 5 2 1.40 Y Y Malignant hypertension 7 9 0.00 Y 0 1 6 6 9 0.00 Y 

Z Primary pulmonary hypertension 7 4 0.71 I 2 4 1 6 4 0.83 I 

AA Mobitz Type 2 Atrioventricular block 7 3 0.71 Y 5 2 0 6 3 0.83 Y 

AB Anomalous atrioventricular excitation 7 3 0.57 Y 5 2 0 6 3 0.67 Y AC Paroxysmal Supraventricular

Tachycardia

7 3 0.86 Y 4 3 0 6 3.5 1.00 Y 

AD Paroxysmal Ventricular Tachycardia 7 5 0.86 Y 1 6 0 6 5 0.83 Y AE Patient with Automatic Implanted

Cardioverter

6 3 1.17 Y 4 2 0 5 3 1.40 Y 

AF Atrial fibrillation 7 3 0.29 Y 7 0 0 6 3 0.33 Y 

AG Atrial flutter in past 6 months 7 3 0.71 Y 5 2 0 6 3 0.83 Y 

AH Persistent severe sinus bradycardia

or sick sinus tachycardia-bradycardia syndrome

7 4 1.00 I 2 4 1 6 4.5 1.33 I 

AI Orthostatic Hypotension 7 2 0.43 Y 6 1 0 6 2 0.50 Y 

AJ Seizure disorder 7 3 0.43 Y 7 0 0 6 2.5 0.50 Y AL Myasthenia gravis 7 3 1.00 Y 5 2 0 6 2.5 1.17 Y 

AM Stroke > 30 days but < 6 months 7 3 1.14 Y 5 2 0 6 3 1.33 Y AN Barbiturate, chlordiazepoxide,

diazepam, glutethimide,meprobamate, or methaqualone 

7 2 0.43 Y 6 1 0 6 2 0.50 Y 

AO Opioid type dependence 7 2 0.43 Y 6 1 0 6 2 0.50 Y 

AP Alcohol abuse 7.195 2.7987 0.62 Y 5 2 0 6 2 0.67 Y 
93 

AMBULATORY S

Patient Characterisitcs #Resp Median Mean Dev Agree? <4 4-6 >6 #Resp Median Mean De

HOSPITAL OUTPATIENT DEPT

AQ Personal history of allergy to

anesthetic agent

7 3 0.43 Y 7 0 0 6 2.5 0.50 Y 

AR Personal history of allergy to narcotic

agent

7 2 0.57 Y 6 1 0 6 2 0.67 Y 

AS Personal history of allergy to

analgesic agent

7 2 0.29 Y 7 0 0 6 2 0.33 Y 

AT History of shock due to anesthesia in

which correct substance was properfly administered

7 4 1.00 Y 3 4 0 6 4 1.17 Y 

AU Anxiety 7 2 0.43 Y 6 1 0 6 2 0.50 Y 

AV Schizophrenic disorder 7 3 0.29 Y 7 0 0 6 3 0.33 Y 

AWEssential, Benign, or Drug-Related

Tremor

7 2 0.29 Y 7 0 0 6 2 0.33 Y 

AX Abnormal head movements,

Fasciculations, Spasms or TremorNot Otherwise Specified

7 3 0.86 Y 4 3 0 6 3 1.00 Y 

AY Mechanical heart valve 6 3 0.33 Y 5 1 0 5 3 0.40 Y BA Un-operated eye has poor vision 7 3 0.43 Y 5 2 0 6 3 0.50 Y 

BB Subluxation of lens 6 5.5 0.67 Y 0 5 1 6 5.5 0.67 Y 

BC Recession of chamber angle 7 5 0.86 I 1 5 1 6 4.5 1.00 Y 

BD Pseudoexfoliation of lens capsule 7 5 0.71 I 1 5 1 6 5 0.83 Y BE Progressive high (degenerative)

myopia/malignant myopia

7 5 0.86 I 1 5 1 6 4.5 1.00 Y 

BF Dislocation of lens 7 7 0.86 Y 0 3 4 6 6.5 1.00 Y BG History of ruptured globe 7 7 1.29 Y 0 2 5 6 7.5 1.50 Y 

BH History of open wound of adnexa 7 3 1.14 Y 4 3 0 6 2.5 1.33 Y 

BI Endothelial corneal dystrophy,

including combined corneal dsystrophy, cornea guttata, andFuch's endothelial dystrophy

7 3 0.57 Y 4 3 0 6 3 0.67 Y 

BJ Posterior synechiae 7 4 1.00 Y 3 4 0 6 3.5 1.17 Y 

BK History of vitrectomy 7 3 0.57 I 4 2 1 6 3 0.67 Y 
94 

SUMMARY OF CATARACT EXPERT PANEL RATINGS FOR PROCEDURE CHARACTE

Procedure Characteristics

# 

Resp

Median Mean 

Dev

Agree 

?

<4 4-6 >6 #

Resp

Median Mean 

Dev

Agre

e ?

<4 4-6 >6 #

Resp

Me

A Cataract surgery requiring general

anesthesia

6 8 1.17 Y 0 1 5 6 7.5 1.17 Y 0 1 5 6 

B Removal of lens material;intracapsular

(66920)

6 9 0.83 Y 0 1 5 6 9 0.83 Y 0 1 5 6 8

C Removal of lens material;

intracapsular, for dislocated lens 

6 9 0.83 Y 0 1 5 6 9 0.83 Y 0 1 5 6 8

D Intracapsular cataract extraction with 

insertion of intraocular lens prothesis(one stage procedure 66983)

6 9 0.83 Y 0 1 5 6 9 0.83 Y 0 1 5 6 8

E Removal of lens material;

phacofragmentation technique (mechanical or ultrasonic), with aspiration (66850)

6 9 0.83 Y 0 1 5 6 9 0.83 Y 0 1 5 6 8

F Extracapsular cataract removal with

insertion of intraocular lens prothesis(one stage procedure), manual ormechanical technique (66984)

6 9 0.83 Y 0 1 5 6 9 0.83 Y 0 1 5 6 8

G Removal of lens material;aspiration 

technique, one or more stages 

(66840)

6 9 0.83 Y 0 1 5 6 9 0.83 Y 0 1 5 6 8

H Removal of lens material; pars plana 

approach, with or without vitrectomy(66852)

6 8.5 2.17 Y 0 1 5 6 8.5 2.17 I 1 1 4 6 7

I Removal of lens 

material;extracapsular (66940)

6 9 0.83 Y 0 1 5 6 9 0.83 Y 0 1 5 6 8

J Removal of implanted material, 

anterior segment of eye (65920)

6 9 0.83 Y 0 1 5 6 9 0.83 Y 0 1 5 6 8

K Expression of lens, linear, one or

more stages (66915)

6 9 0.83 Y 0 1 5 6 9 0.83 Y 0 1 5 6 8

L Repositioning of intraocular lens 

prosthesis, requiring an incision, complication (66825)

6 9 0.83 Y 0 1 5 6 9 0.83 Y 0 1 5 6 8

M Procedure performed by resident 6 8.5 0.67 Y 0 1 5 6 8 0.50 Y 0 0 6 6 

HOSPITAL OUTPATIENT DEPARTMENT

NORMAL OR VERY LOW RISK LOW-MODERATE RISK 
95 

# 

Resp

Median Mean 

Dev

Agree 

?

<44-6>6 # 

Resp

Median Mean

Dev

Agree

?

<44-6>6 # 

Re

5 6 1.60 Y 0 3 2 5 6 1.40 I 1 2 2 5 5 9 1.00 Y 0 1 4 5 9 1.00 Y 0 1 4 5 5 9 1.00 Y 0 1 4 5 9 1.00 Y 0 1 4 5 5 9 1.00 Y 0 1 4 5 9 1.00 Y 0 1 4 5 5 9 1.00 Y 0 1 4 5 9 1.00 Y 0 1 4 5 5 9 1.00 Y 0 1 4 5 9 1.00 Y 0 1 4 5 5 9 1.00 Y 0 1 4 5 9 1.00 Y 0 1 4 5 5 5 1.40 Y 0 3 2 5 5 1.40 Y 0 3 2 5 5 9 1.00 Y 0 1 4 5 9 1.00 Y 0 1 4 5 5 9 1.00 Y 0 1 4 5 9 1.00 Y 0 1 4 5 5 9 1.00 Y 0 1 4 5 9 1.00 Y 0 1 4 5 5 9 1.00 Y 0 1 4 5 9 1.00 Y 0 1 4 5 5 9 0.60 Y 0 0 5 5 8 0.60 Y 0 0 5 5 

NORMAL or VERY LOW RISK LOW-MODERATE RISK 

Procedure Characteristics

A Cataract surgery requiring general

anesthesia

B Removal of lens material;intracapsular 

(66920)

C Removal of lens material;

intracapsular, for dislocated lens 

D Intracapsular cataract extraction with

insertion of intraocular lens prothesis(one stage procedure 66983)

E Removal of lens material;

phacofragmentation technique (mechanical or ultrasonic), withaspiration (66850)

F Extracapsular cataract removal with

insertion of intraocular lens prothesis(one stage procedure), manual ormechanical technique (66984)

G Removal of lens material;aspiration 

technique, one or more stages 

(66840)

H Removal of lens material; pars plana 

approach, with or without vitrectomy(66852)

I Removal of lens 

material;extracapsular (66940)

J Removal of implanted material,

anterior segment of eye (65920)

K Expression of lens, linear, one or 

more stages (66915)

L Repositioning of intraocular lens 

prosthesis, requiring an incision,complication (66825)

M Procedure performed by resident
96 

SUMMARY OF CATARACT EXPERT PANEL RATINGS FOR PATIENT OUTCOME

CATARACT OUTCOMES

# Resp Median Mean Dev Agree? <4 4-6 >6 #Resp Median Mean Dev 

A Arrhythmia 6 3 1.00 I 4 1 1 6 5 0.50 B Capsule rupture or posterior capsule tear 6 5.5 1.17 I 1 3 2 6 4 0.83 C New or Worsening Congestive heart failure 6 6 1.50 N 2 2 2 6 7 0.67 D Persistent cystoid macular edema (Diabetic vs. nondiabetic) 5 5 0.80 Y 0 3 2 5 6 0.80 

E Death 6 5.5 1.17 Y 0 4 2 6 9 0.00 F Endophthalmitis 5 7 0.80 Y 0 2 3 6 8.5 0.50 G Hypertension 6 6 0.50 Y 0 5 1 6 4 1.33 H Hypotension 6 5 1.00 Y 0 4 2 6 5 0.33 I Iris prolapse 6 8 0.33 Y 0 1 5 6 5 1.00 J Myocardial infarction 6 4 1.17 I 2 3 1 6 9 0.50 K Retained nuclear fragment (posterior chamber vs.

anterior chamber) 6 8 1.00 Y 0 2 4 6 5.5 0.50 

L Ocular hypertension 6 6 0.50 Y 0 5 1 6 4 0.67 M Persistent iridocyclitis 6 6 0.67 Y 0 4 2 6 6 0.50 N Poor ocular motility, excluding cranial VII palsy 6 6 0.67 Y 0 4 2 5 5 0.40 O Retinal break 6 4.5 1.33 Y 2 4 0 7 7 1.00 P Retinal detachment (complicated versus 

uncomplicated surgery) 6 4.5 1.17 Y 2 4 0 7 8 0.29 

Q Stroke 6 4 1.67 I 3 2 1 7 8 0.29 R Wound dehiscence 7 6 1.00 I 1 3 3 7 7 0.43 S Wound leak 7 8 0.43 Y 0 1 6 6 6.5 0.67 T Aspiration pneumonia 5 7 2.20 N 2 0 3 6 7 0.33 U Respiratory Failure From Surgery 5 5 1.60 I 2 2 1 6 8 0.67 V Hyphema 6 6.5 0.67 Y 0 3 3 6 5 0.67 W Persistent Corneal Edema 6 7 0.50 Y 0 1 5 6 7 0.33 X Vitreous Loss 6 6.5 1.00 I 1 2 3 6 5.5 1.00 Y Secondary Glaucoma 6 5.5 0.83 Y 0 4 2 5 6 0.40 Z Dislocated Ocular Lenses 6 7.5 0.83 Y 0 1 5 6 5.5 0.83 AAIris/pupil deformation 6 7 0.67 Y 0 1 5 6 5 0.67 

PREVENTABLE SEVER
97 

APPENDIX D. EXPERT PANEL ON COLONOSCOPY 

February 2, 2004 

Dr. Ron Fogel 

Division of Gastroenterology 

Henry Ford Hospital 

2799 West Grand Blvd. 

Detroit, Ml 48202 

Dr. David A. Lieberman, M.D. 

Portland VA Medical Center 

3710 SW US Veterans Hospital Rd. 

Portland, OR 97201 

Ms. Pat Maher RN CGRN 

Saint Joseph Health Center Endoscopy 

300 First Capital Drive 

Saint Charles, MO 63301 

Dr. Martin C. Mahoney, MD, Ph.D., 

FAAFP 

Chair, Clinical Prevention 

Division of Cancer Prevention & 

Population Sciences 

Roswell Park Cancer Institute 

Elm & Carlton Streets 

Buffalo, NY 14263 

Dr. Peter M. Pardoll 

Center for Digestive Disease 

1609 Pasadena Ave., South Suite 3M 

St. Petersburg, FL 33707 

Dr. Bart Pope 

LSUMC Shreveport 

PO Box 33932 

Shreveport, LA 71130-3932 

Facilitator: Dr. Steven Asch, RAND 

Dr. Douglas K. Rex, M.D. 

Indiana University Medical Center 

550 North University Blvd., #2300 

Indianapolis, IN 46202 

Dr. Allison Rosen, MD 

Division of General Medicine and Primary 

Care 

Beth Israel Deaconess Medical Center 

330 Brookline Avenue, Rose 130 

Boston, MA 02215 

Dr. Anthony Senagore 

Cleveland Clinic Foundation -- A-30 

9500 Euclid Avenue 

Cleveland, OH 44195-0001 
98 

COLONOSCOPY RATING FORMS AND EXPERT PANEL PROCESS 

A. Outcomes/complications, round “0” (first-round): preventability and severity. 

Panelist provided ratings prior to the panel discussion and faxed their responses. The 

panelists’ responses were entered into a database. 

B. Outcomes/complications, round “1” (second-round) with rating summary: 

preventability and severity. Panelists received the rating form and a summary of the 

scores for each indicator. Panelists completed the rating form again during the panel 

discussion. 

C. Patient characteristics: risk. Panelists completed this rating form during the panel 

discussion. 

D. Procedure characteristics: appropriateness across outpatient settings. Panelists 

briefly discussed procedure characteristics, but completed the rating form after the 

panel discussion because of time constraints. 
99 

SUMMARY OF COLONOSCOPY EXPERT PANEL RATINGS FOR PATIENT CHARACTERISTICS 

Patient Characteristics

# Resp Median Mean

Dev

Agree? 123456789 <4 4-6 >6

A Age > 70 years 9 1 0.33 Y 630000000 9 0 0

B Age > 85 years 9 2 0.22 Y 261000000 9 0 0

C Stable angina 9 2 0.22 Y 360000000 9 0 0

D Unstable angina in last 3 months 9 3 0.67 Y 124200000 7 2 0

E Myocardial infarction within past 7

days

9 4 0.89 I 003311100 3 5 1

F Recent myocardial infarction (> 7 

days but fewer than 30 days)

9 3 1.00 Y 032211000 5 4 0

G Myocardial infarction (>30 days but

fewer than 6 months)

9 3 0.67 Y 133200000 7 2 0

H Old myocardial infarction (> 6 

months)

8 2 0.25 Y 350000000 8 0 0

I Dementia 8 2 0.88 Y 322010000 7 1 0

J Chronic obstructive pulmonary

disease with hospitalization or

emergency department visit within

past one year

8 2 0.50 Y 052100000 7 1 0

K Asthma with hospitalization or

emergency department visit within

8 2 0.13 Y 170000000 8 0 0

L Bronchietasis with acute 

exacerbation within past 6 months

8 2 0.50 Y 052100000 7 1 0

M Cirrhosis 8 1.5 1.06 Y 412010000 7 1 0

N Cardiomyopathy/heart

failure/pulmonary edema with

hospitalization or emergency

department visit within past one year

8 3 0.50 Y 033200000 6 2 0

O Orthopnea 9 3 1.00 I 014300010 5 3 1

P History of bleeding disorder 9 3 0.67 Y 134010000 8 1 0

Q History of adverse effect from 

anticoagulation in past 3 months

9 2 0.56 Y 243000000 9 0 0

R Diabetes mellitus (Type 2), requiring 

insulin

9 1 0.33 Y 630000000 9 0 0

S Diabetes mellitus (Type 2), not 

requiring insulin

4 1.5 0.38 Y 220000000 4 0 0

T Chronic renal failure, requiring

hemodialysis

9 2 0.67 Y 431100000 8 1 0

U Chronic renal failure, not requiring

hemodialysis

9 2 0.44 Y 441000000 9 0 0

V Aortic stenosis 9 2 0.78 Y 331200000 7 2 0

W Malnutrition 9 2 0.33 Y 450000000 9 0 0

X Thyrotoxicosis within past 6 months 9 2 0.22 Y 360000000 9 0 0

Y Malignant hypertension 9 3 1.67 N 122020110 5 2 2

Z Primary pulmonary hypertension 9 3 1.00 Y 122220000 5 4 0

HOSPITAL OUTPATIENT DEPT
100 

Patient Characteristics

# Resp Median Mean

Dev

Agree? 123456789 <4 4-6 >6

HOSPITAL OUTPATIENT DEPT

AA Mobitz Type 2 Atrioventricular block 9 2 0.44 Y 062100000 8 1 0

AB Anomalous atrioventricular excitation 

including:accelerated, accessory

ventricular pre-excitation, WolffParkinson-White syndrome

9 2 0.33 Y 063000000 9 0 0

AC Paroxysmal Supraventricular

Tachycardia

9 2 0.22 Y 162000000 9 0 0

AD Paroxysmal Ventricular Tachycardia 9 3 0.67 Y 034020000 7 2 0

AE Patient with Automatic Implanted 

Cardioverter Defibrillator (AICD)

9 2 0.67 Y 143100000 8 1 0

AF Atrial fibrillation 9 2 0.67 Y 432000000 9 0 0

AG Atrial flutter in past 6 months 9 1 0.44 Y 531000000 9 0 0

AH Persistent severe sinus bradycardia

or sick sinus tachycardia-bradycaridia 

syndrome

9 3 1.11 I 043010010 7 1 1

AI Orthostatic Hypotension 9 2 0.89 I 152000100 8 0 1

AJ Seizure disorder 9 2 0.44 Y 450000000 9 0 0

AK Myasthenia gravis 9 2 0.78 Y 431010000 8 1 0

AL Stroke within past 6 months 9 2 0.56 Y 333000000 9 0 0

AM Barbiturate, chlordiazepoxide,

diazepam, glutethimide,

meprobamate, or methaqualone 

dependence

9 2 0.44 Y 350100000 8 1 0

AN Opioid type dependence 9 2 0.67 Y 350001000 8 1 0

AO Alcohol abuse 9 2 0.44 Y 342000000 9 0 0

AP Personal history of allergy to

anesthetic agent

9 2 0.56 Y 243000000 9 0 0

AQ Personal history of allergy to narcotic

agent

9 2 0.22 Y 171000000 9 0 0

AR Personal history of allergy to

analgesic agent

9 2 0.11 Y 180000000 9 0 0

AS History of shock due to anesthesia in

which correct substance was properly

administered

9 3 0.56 Y 035010000 8 1 0

AT Anxiety 9 1 0.56 Y 531000000 9 0 0

AU Schizophrenic disorder 9 2 0.67 Y 431100000 8 1 0

AV Mechanical heart valve 9 1 0.56 Y 531000000 9 0 0

BA History of partial bowel obstruction 9 2 0.44 Y 450000000 9 0 0

BB History of complete bowel obstruction 9 2 0.44 Y 351000000 9 0 0

BC History of colorectal cancer 9 2 0.44 Y 450000000 9 0 0

BD History of prior GI workup (other GI

procedures including other

endoscopy or radiological GI studies

9 1 0.33 Y 540000000 9 0 0

BE Inflammatory bowel disease 9 2 0.44 Y 450000000 9 0 0

BF Melena 9 2 0.22 Y 171000000 9 0 0
101 

# Resp Median Mean

Dev

Agree? 1234 5 6 7 8 9 <4 4-6 >6

ASC

Patient Characteristics

AA Mobitz Type 2 Atrioventricular block

AB Anomalous atrioventricular excitation

including:accelerated, accessory

ventricular pre-excitation, WolffParkinson-White syndrome

AC Paroxysmal Supraventricular

Tachycardia

AD Paroxysmal Ventricular Tachycardia

AE Patient with Automatic Implanted

Cardioverter Defibrillator (AICD)

AF Atrial fibrillation

AG Atrial flutter in past 6 months

AH Persistent severe sinus bradycardia 

or sick sinus tachycardiabradycaridia syndrome

AI Orthostatic Hypotension

AJ Seizure disorder

AK Myasthenia gravis

AL Stroke within past 6 months

AM Barbiturate, chlordiazepoxide,

diazepam, glutethimide,

meprobamate, or methaqualone

dependence

AN Opioid type dependence

AO Alcohol abuse

AP Personal history of allergy to

anesthetic agent

AQ Personal history of allergy to narcotic

agent

AR Personal history of allergy to

analgesic agent

AS History of shock due to anesthesia in

which correct substance was 

properly administered

AT Anxiety

AU Schizophrenic disorder

AV Mechanical heart valve

BA History of partial bowel obstruction

BB History of complete bowel

obstruction

BC History of colorectal cancer

BD History of prior GI workup (other GI

procedures including other

endoscopy or radiological GI studies

BE Inflammatory bowel disease

BF Melena

9 2 0.56 Y 0 6 1 2 0 0 0 0 0 7 2 0

9 3 0.44 Y 0 4 5 0 0 0 0 0 0 9 0 0

9 2 0.56 Y 1 5 2 1 0 0 0 0 0 8 1 0

9 3 0.89 Y 0 3 4 0 1 1 0 0 0 7 2 0

9 3 0.89 Y 1 3 4 0 0 1 0 0 0 8 1 0

8 2 0.63 Y 3 3 2 0 0 0 0 0 0 8 0 0

9 1 0.56 Y 5 3 1 0 0 0 0 0 0 9 0 0

9 3 1.33 I 0 3 3 0 2 0 0 1 0 6 2 1

9 2 1.22 I 1 4 2 0 1 0 1 0 0 7 1 1

9 2 0.44 Y 4 5 0 0 0 0 0 0 0 9 0 0

9 2 0.89 Y 4 3 1 0 1 0 0 0 0 8 1 0

9 2 0.67 Y 3 3 3 0 0 0 0 0 0 9 0 0

9 2 0.67 Y 3 4 1 1 0 0 0 0 0 8 1 0

9 2 0.89 Y 3 4 1 0 0 1 0 0 0 8 1 0

9 2 0.56 Y 3 4 2 0 0 0 0 0 0 9 0 0

9 2 0.89 Y 2 3 2 2 0 0 0 0 0 7 2 0

9 2 0.33 Y 1 6 2 0 0 0 0 0 0 9 0 0

9 2 0.22 Y 1 7 1 0 0 0 0 0 0 9 0 0

9 3 0.56 Y 0 2 5 1 1 0 0 0 0 7 2 0

9 1 0.56 Y 5 3 1 0 0 0 0 0 0 9 0 0

9 2 0.78 Y 4 3 1 1 0 0 0 0 0 8 1 0

9 1 0.56 Y 5 3 1 0 0 0 0 0 0 9 0 0

9 2 0.44 Y 4 5 0 0 0 0 0 0 0 9 0 0

9 2 0.44 Y 3 5 1 0 0 0 0 0 0 9 0 0

9 2 0.44 Y 4 5 0 0 0 0 0 0 0 9 0 0

9 1 0.44 Y 5 4 0 0 0 0 0 0 0 9 0 0

9 2 0.44 Y 4 5 0 0 0 0 0 0 0 9 0 0

9 2 0.44 Y 0 6 2 1 0 0 0 0 0 8 1 0
102 

# Resp Median Mean 

Dev

Agree? 1 234 5 6 789 <4 4-6 >6

9 1 0.89 Y 5 2 100 000 0 8 1 0

9 2 1.11 I 1 5 101 000 0 7 1 1

8 2 0.38 Y 1 5 201 010 0 8 0 0

8 3.5 1.38 I 0 2 220 000 0 4 3 1

9 6 1.78 I 0 1 001 001 0 1 4 4

9 4 1.44 N 0 1 143 111 2 2 5 2

9 3 1.44 N 0 3 401 001 1 7 0 2

8 2 0.38 Y 3 5 000 002 0 8 0 0

8 2.5 1.75 I 2 2 110 000 0 5 2 1

8 3 0.88 Y 0 2 311 001 0 5 3 0

8 2 0.50 Y 0 5 212 000 0 7 1 0

8 3.5 1.00 Y 0 3 130 000 0 4 4 0

8 1.5 1.88 I 4 1 011 000 0 5 2 1

8 4.5 1.00 I 0 0 221 001 0 2 5 1

9 5 1.44 I 0 0 133 010 0 1 6 2

9 4 1.67 N 0 1 232 101 1 3 4 2

9 3 0.89 Y 1 3 311 000 2 7 2 0

9 1 0.33 Y 6 3 001 000 0 9 0 0

4 1.5 0.50 Y 2 2 000 000 0 4 0 0

9 2 1.78 I 4 1 110 000 0 6 2 1

9 2 0.56 Y 4 4 100 110 0 9 0 0

9 4 1.89 I 3 1 020 000 0 4 4 1

9 2 0.78 Y 4 3 111 110 0 8 1 0

9 2 0.67 I 3 4 110 000 0 8 1 0

9 5 2.00 I 1 1 110 000 0 3 4 2

9 5 1.11 N 0 2 012 101 1 2 6 1

PHYSICIAN OFFICE

Patient Characteristics

A Age > 70 years

B Age > 85 years

C Stable angina

D Unstable angina in last 3 months

E Myocardial infarction within past 7

days

F Recent myocardial infarction (> 7 

days but fewer than 30 days)

G Myocardial infarction (>30 days but

fewer than 6 months)

H Old myocardial infarction (> 6 

months)

I Dementia

J Chronic obstructive pulmonary

disease with hospitalization or

emergency department visit within

past one year

K Asthma with hospitalization or

emergency department visit within

L Bronchietasis with acute

exacerbation within past 6 months

M Cirrhosis

N Cardiomyopathy/heart 

failure/pulmonary edema with 

hospitalization or emergency

department visit within past one 

year

O Orthopnea

P History of bleeding disorder

Q History of adverse effect from 

anticoagulation in past 3 months

R Diabetes mellitus (Type 2), requiring 

insulin

S Diabetes mellitus (Type 2), not

requiring insulin

T Chronic renal failure, requiring

hemodialysis

U Chronic renal failure, not requiring

hemodialysis

V Aortic stenosis

W Malnutrition

X Thyrotoxicosis within past 6 months

Y Malignant hypertension

Z Primary pulmonary hypertension
103 

# Resp Median Mean

Dev

Agree? 1 2 3 4 5 6 789 <4 4-6 >6

PHYSICIAN OFFICE

Patient C haracteristics

9 3 1.00 Y 0 232 411 005 4 0

9 3 0.56 Y 0 152 110 006 3 0

9 3 0.78 Y 0 431 100 007 2 0

9 3 2.00 N 0 230 100 005 2 2

9 5 2.33 N 1 120 200 024 2 3

7 2 1.14 Y 3 120 201 026 1 0

8 2 0.50 Y 3 410 100 008 0 0

9 4 2.11 N 0 212 000 003 3 3

9 3 1.33 I 0 420 101 026 2 1

9 2 0.78 Y 4 230 201 009 0 0

9 2 1.44 I 4 220 000 008 0 1

9 2 1.00 Y 3 230 000 018 1 0

9 2 1.00 I 1 520 100 008 0 1

9 2 1.11 Y 1 510 000 107 2 0

9 2 1.22 Y 2 320 020 007 2 0

9 2 1.44 Y 2 302 110 005 4 0

9 2 0.78 Y 1 511 110 007 2 0

9 2 0.44 Y 1 611 100 008 1 0

9 4 1.67 N 0 131 000 004 3 2

9 1 0.56 Y 5 310 201 019 0 0

9 2 1.33 Y 4 220 000 008 0 1

9 1 0.56 Y 5 310 000 109 0 0

9 2 0.89 Y 3 312 000 007 2 0

9 2 0.78 Y 3 240 000 009 0 0

9 2 0.44 Y 4 500 000 009 0 0

9 1 0.44 Y 5 400 000 009 0 0

9 2 0.56 Y 4 410 000 009 0 0

9 4 1.33 I 0 122 000 003 5 1

AA Mobitz Type 2 Atrioventricular block

AB Anomalous atrioventricular excitation

including:accelerated, accessory

ventricular pre-excitation, W olffParkinson-W hite syndrome

AC Paroxysmal Supraventricular

Tachycardia

AD Paroxysmal Ventricular Tachycardia

AE Patient with Automatic Implanted

Cardioverter Defibrillator (AICD)

AF Atrial fibrillation

AG Atrial flutter in past 6 months

AH Persistent severe sinus bradycardia 

or sick sinus tachycardia-bradycaridia

syndrome

AI Orthostatic Hypotension

AJ Seizure disorder

AK Myasthenia gravis

AL Stroke within past 6 months

AM Barbiturate, chlordiazepoxide,

diazepam, glutethimide,

meprobamate, or methaqualone

AN Od d pioid type dependence

AO Alcohol abuse

AP Personal history of allergy to

anesthetic agent

AQ Personal history of allergy to narcotic

agent

AR Personal history of allergy to

analgesic agent

AS History of shock due to anesthesia in

which correct substance was properly

administered

AT Anxiety

AU Schizophrenic disorder

AV Mechanical heart valve

BA History of partial bowel obstruction

BB History of complete bowel obstruction

BC History of colorectal cancer

BD History of prior GI workup (other GI

procedures including other

endoscopy or radiological GI studies

BE Inflammatory bowel disease

BF Melena
104 

SUMMARY OF COLONOSCOPY EXPERT PANEL RATINGS FOR PROCEDURE CHARACT

Procedure Characteristics

# 

Resp

Median Mean

Dev

Agree

?

123 456789 <4 4

A Colonoscopy with biopsy 9 9 0.56 Y 000 010017 0 1 B Colonoscopy for foreign body 9 9 0.56 Y 000 010017 0 1 C Colonoscopy for bleeding 9 9 0.56 Y 000 010017 0 1 D Colonoscopy with polypectomy NOT

involving the ascending colon 9 9 0.56 Y 000 010017 0 1 

E Colonoscopy with polypectomy involving

the ascending colon 9 9 0.33 Y 000 000117 0 0 

F Colonoscopy with snare 9 9 0.44 Y 000 001017 0 1 G Colonoscopy with stent 9 9 0.44 Y 000 001017 0 1 I Diagnostic colonoscopy with no

additional procedures performed duringprocedure 9 9 0.56 Y 000 000216 0 0 

J Colonoscopy with submucous injection 9 9 0.44 Y 000 000126 0 0 K Colonoscopy with lesion removal 9 9 0.33 Y 000 000117 0 0 L Colonoscopy with dilation of stricture

under fluoroscopy 9 9 0.44 Y 000 000126 0 0 

M Colonoscopy with dilation of stricture

without fluoroscopy 9 9 1.22 I 001 010016 1 1 

N Colonoscopy with endoscopic mucosal

resection 9 9 0.44 Y 000 001017 0 1 

O Colonoscopy performed by physician in

training 9 9 0.11 Y 000 000018 0 0 

NORMAL OR VERY LOW RISK
105 

# Resp Median Mean

Dev

Agree ? 1 234567 8 9 <4 4-6 >6 #

Resp

Median Mean 

Dev

Agree ? 1

9 9 0.33 Y 0 000001 1 7 0 0 9 9 9 0.22 Y 09 9 0.33 Y 0 000001 1 7 0 0 9 9 9 0.22 Y 09 9 0.33 Y 0 000001 1 7 0 0 9 9 9 0.22 Y 09 9 0.33 Y 0 000001 1 7 0 0 9 9 9 0.22 Y 09 9 0.56 Y 0 000100 1 7 0 1 8 9 9 0.67 Y 09 9 0.44 Y 0 000010 1 7 0 1 8 9 9 0.56 Y 09 9 0.56 Y 0 000100 1 7 0 1 8 9 9 1.22 Y 09 9 0.78 Y 0 000101 1 6 0 1 8 9 9 1.11 Y 09 9 0.56 Y 0 000010 2 6 0 1 8 9 9 0.78 Y 09 9 0.44 Y 0 000010 1 7 0 1 8 9 9 0.67 Y 09 9 0.44 Y 0 000001 2 6 0 0 9 9 9 0.44 Y 09 9 1.22 I 0 010100 1 6 1 1 7 9 9 1.33 I 09 9 0.56 Y 0 000011 0 7 0 1 8 9 9 0.56 09 9 0.22 Y 0 000001 0 8 0 0 9 9 9 0.78 Y 0

LOW-MODERATE RISK MODERA

HOSPITAL OUTPATIENT DEPARTMENT

Procedure Characteristics

A Colonoscopy with biopsyB Colonoscopy for foreign bodyC Colonoscopy for bleedingD Colonoscopy with polypectomy NOT

involving the ascending colon

E Colonoscopy with polypectomy involving

the ascending colon

F Colonoscopy with snareG Colonoscopy with stentI Diagnostic colonoscopy with no additional

procedures performed during procedure

J Colonoscopy with submucous injectionK Colonoscopy with lesion removalL Colonoscopy with dilation of stricture 

under fluoroscopy

M Colonoscopy with dilation of stricture 

without fluoroscopy

N Colonoscopy with endoscopic mucosal

resection

O Colonoscopy performed by physician in

training
106 

Procedure Characteristics

A Colonoscopy with biopsyB Colonoscopy for foreign bodyC Colonoscopy for bleedingD Colonoscopy with polypectomy NOT 

involving the ascending colon

E Colonoscopy with polypectomy involving

the ascending colon

F Colonoscopy with snareG Colonoscopy with stentI Diagnostic colonoscopy with no additional

procedures performed during procedure

J Colonoscopy with submucous injectionK Colonoscopy with lesion removalL Colonoscopy with dilation of stricture 

under fluoroscopy

M Colonoscopy with dilation of stricture 

without fluoroscopy

N Colonoscopy with endoscopic mucosal

resection

O Colonoscopy performed by physician in

training

# 

Resp

Median Mean 

Dev

Agree ? 1 2345678 9 <4 4-6 >6 # Resp Median Mean 

Dev

Agree? 1

9 9 0.22 Y 0 0000002 5 0 2 7 9 9 0.22 Y 09 9 0.89 Y 0 0001012 3 0 3 6 9 9 1.00 Y 08 9 0.63 Y 0 0000021 3 0 2 6 8 9 1.00 Y 09 9 0.44 Y 0 0000012 4 0 2 7 9 9 0.78 Y 09 9 0.33 Y 0 0000011 5 0 2 7 9 9 0.33 Y 09 9 0.33 Y 0 0000011 5 0 2 7 9 9 0.33 Y 09 9 1.22 Y 0 0020001 4 0 4 5 9 9 1.33 I 09 9 0.33 Y 0 0000011 5 0 2 7 9 9 0.33 Y 09 9 0.67 Y 0 0010001 5 0 3 6 9 9 0.89 I 09 9 0.78 I 0 0100001 5 1 2 6 9 9 0.89 I 09 9 1.11 I 0 0100011 4 1 2 6 9 9 1.00 I 09 9 1.67 N 0 0200011 3 2 2 5 9 9 1.78 N 09 9 1.22 I 0 1000011 4 1 2 6 9 9 1.11 I 09 9 0.56 Y 0 0000021 4 0 2 7 9 9 0.56 Y 0

NORMAL or VERY LOW RISK

 PROCEDURE PERFORMED IN AN AMBULATORY SURGERY CENTE

LOW-MODE
107 

# 

Resp

Median Mean

Dev

Agree

?

1 2345 6789 <4 4-6 >6 #

Resp

Median Mean

Dev

Agree

?

9 9 0.44 Y 0 0000 1017 0 1 8 9 9 0.44 Y 9 8 1.11 Y 0 0002 0034 0 2 7 9 8 2.67 N 8 8.5 1.13 Y 0 0010 0115 0 1 7 9 7 2.44 N 9 9 0.67 Y 0 0001 0026 0 1 8 9 9 2.78 N 9 9 0.33 Y 0 0000 0117 0 0 9 8 8.5 1.38 Y 9 9 0.44 Y 0 0000 0126 0 0 9 8 8.5 1.50 Y 9 8 1.78 I 0 1010 0115 1 1 7 8 5 3.25 N 9 9 0.56 Y 0 0001 0017 0 1 8 9 8 1.33 I 9 9 0.89 I 0 1000 0017 1 0 8 9 9 2.33 N 9 9 1.00 I 0 1000 0026 1 0 8 9 8 1.78 I 9 8 1.22 I 0 1000 0134 1 0 8 9 4 2.33 N 9 8 1.78 N 0 1100 0124 2 0 7 9 4 2.22 N 9 9 1.22 I 0 1000 0125 1 0 8 9 5 2.44 N 9 9 0.56 Y 0 0000 0216 0 0 9 9 9 1.00 I 

MODERATE RISK NORMAL OR 

R

Procedure Characteristics

A Colonoscopy with biopsyB Colonoscopy for foreign bodyC Colonoscopy for bleedingD Colonoscopy with polypectomyNOT

involving the ascending colon

E Colonoscopy with polypectomyinvolving

the ascending colon

F Colonoscopy with snareG Colonoscopy with stentI Diagnostic colonoscopy with no

additional procedures performed duringprocedure

J Colonoscopy with submucous injectionK Colonoscopy with lesion removalL Colonoscopy with dilationof stricture

under fluoroscopy

M Colonoscopy with dilationof stricture

without fluoroscopy

N Colonoscopy with endoscopic mucosal 

resection

O Colonoscopy performed byphysician in

training
108 

# 

Resp

Median Mean

Dev

Agree

?

1 23456 789 <4 4-6 >6 #

Resp

Median Mean

Dev

Agre

?

9 8 0.56 Y 0 00000 144 0 0 9 9 7 1.67 I 9 7 2.44 N 1 20001 221 3 1 5 9 5 2.22 N 8 7 2.25 N 0 20002 022 2 2 4 8 5 2.75 N 9 8 2.78 N 1 01010 033 2 1 6 9 5 2.56 N 8 8 1.38 Y 0 00030 032 0 3 5 8 5.5 1.88 N 8 8 1.50 Y 0 00030 023 0 3 5 8 6 2.00 I 8 4 2.75 N 2 11011 011 4 2 2 8 2.5 1.75 I 9 8 1.56 I 0 10000 224 1 0 8 9 7 2.00 N 9 8 2.33 N 2 00001 024 2 1 6 9 7 2.67 N 9 8 1.67 I 1 00002 114 1 2 6 9 7 2.22 N 9 3 2.11 N 4 01001 021 5 1 3 9 2 2.11 N 9 3 2.00 N 3 02001 012 5 1 3 9 3 2.67 N 9 4 2.22 N 3 01100 112 4 1 4 9 4 2.67 N 9 8 1.33 I 0 01010 133 1 1 7 9 6 1.33 I 

MOD

PROCEDURE PERFORMED IN A PHYSICIAN OFFICE

LOW-MODERATE RISK

Procedure Characteristics

A Colonoscopy with biopsyB Colonoscopy for foreign bodyC Colonoscopy for bleedingD Colonoscopy with polypectomy NOT

involving the ascending colon

E Colonoscopy with polypectomy involving 

the ascending colon

F Colonoscopy with snareG Colonoscopy with stentI Diagnostic colonoscopy with no

additional procedures performed duringprocedure

J Colonoscopy with submucous injectionK Colonoscopy with lesion removalL Colonoscopy with dilation of stricture 

under fluoroscopy

M Colonoscopy with dilation of stricture 

without fluoroscopy

N Colonoscopy with endoscopic mucosal

resection

O Colonoscopy performed by physician in

training
109 

SUMMARY OF COLONOSCOPY EXPERT PANEL RATINGS FOR PATIENT OUTCO

Outcomes

# Resp Median Mean Dev Agree? 1 2 3 4 5 6 7 8 9 

A Abdominal pain 9 5 0.33 Y 0 0 0 0 6 3 0 0 0 B Altered mental status 9 6 1.56 I 0 0 1 1 2 2 0 2 1 C Arrhythmia 9 2 1.00 Y 2 3 211 0 0 0 0 D Chest pain 9 4 1.44 Y 1 2 113 1 0 0 0 E Death 9 8 1.56 I 0 1 010 0 1 3 3 F Dyspnea 9 7 1.89 N 0 2 1 0 0 1 4 0 1 G Hemorrhage 9 5 1.56 N 0 2 0 0 3 0 4 0 0 H Hypertension 9 6 1.11 I 0 1 012 3 2 0 0 I Hypotension 9 4 1.56 N 0 2 2 1 2 0 2 0 0 J Hypoxia 9 5 2.11 N 0 1 301 1 0 3 0 K Perforation 9 5 2.33 N 0 3 0 0 2 0 0 4 0 L Post-polypectomy syndrome 9 5 1.56 I 0 3 0 0 3 2 0 1 0 A Abdominal distension 9 5 0.78 I 0 0 1 0 4 3 1 0 0 B Endocarditis 9 6 1.67 N 0 2 001 2 3 0 1 C Sepsis and other infections 9 7 1.44 N 0 2 0 0 0 2 4 1 0 D Small bowel obstruction 9 2 0.67 Y 1 5 2 0 1 0 0 0 0 E Splenic rupture 9 5 2.22 N 0 3 002 0 1 3 0 F Splenic trauma 9 5 2.22 N 0 3 0 0 2 0 1 3 0 G Vasovagal reactions 9 4 1.56 I 1 2 1 1 3 0 1 0 0 

PREVENTABLE
110 

Outcomes

A Abdominal painB Altered mental statusC ArrhythmiaD Chest painE DeathF DyspneaG HemorrhageH HypertensionI HypotensionJ HypoxiaK PerforationL Post-polypectomy syndromeA Abdominal distensionB EndocarditisC Sepsis and other infectionsD Small bowel obstructionE Splenic ruptureF Splenic traumaG Vasovagal reactions

# Resp Median Mean Dev Agree? 12345 6 7 8 

7 2 0.29 Y 05200 0 0 08 2.5 1.00 Y 13211 0 0 08 3.5 1.25 Y 02212 1 0 07 6 1.29 I 00201 3 0 18 9 0.00 Y 00000 0 0 08 4 1.13 N 00231 0 2 08 6.5 1.00 Y 00003 1 3 18 3 1.50 N 02310 0 1 18 6.5 1.50 I 00111 1 2 28 7 0.75 Y 00001 0 4 28 9 0.63 Y 00000 1 0 28 7 0.88 Y 00001 2 2 38 4 0.88 I 00241 0 0 18 8 0.44 Y 00000 0 0 47 8 0.57 Y 00000 1 2 48 7 0.88 Y 00000 3 2 27 9 0.29 Y 00000 0 0 27 8 0.43 Y 00000 0 0 48 5 1.38 Y 00032 1 0 1

SEVERITY
111 

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