Department of Health and Human Services
 

OFFICE OF 

INSPECTOR GENERAL 

MEDICARE PAYMENTS FOR 


FACET JOINT INJECTION 


SERVICES
 

Daniel R. Levinson
 

Inspector General 


September 2008
 

OEI-05-07-00200
 
 

 

 

 

 

 

 

Office of Inspector General
 http://oig.hhs.gov 

The mission of the Office of Inspector General (OIG), as mandated by Public Law 95-452, as 

amended, is to protect the integrity of the Department of Health and Human Services 

(HHS) programs, as well as the health and welfare of beneficiaries served by those 

programs. This statutory mission is carried out through a nationwide network of audits, 

investigations, and inspections conducted by the following operating components: 

Office of Audit Services 

The Office of Audit Services (OAS) provides auditing services for HHS, either by conducting 

audits with its own audit resources or by overseeing audit work done by others. Audits 

examine the performance of HHS programs and/or its grantees and contractors in carrying 

out their respective responsibilities and are intended to provide independent assessments of 

HHS programs and operations. These assessments help reduce waste, abuse, and 

mismanagement and promote economy and efficiency throughout HHS. 

Office of Evaluation and Inspections 

The Office of Evaluation and Inspections (OEI) conducts national evaluations to provide 

HHS, Congress, and the public with timely, useful, and reliable information on significant 

issues. These evaluations focus on preventing fraud, waste, or abuse and promoting 

economy, efficiency, and effectiveness of departmental programs. To promote impact, OEI 

reports also present practical recommendations for improving program operations. 

Office of Investigations 

The Office of Investigations (OI) conducts criminal, civil, and administrative investigations 

of fraud and misconduct related to HHS programs, operations, and beneficiaries. With 

investigators working in all 50 States and the District of Columbia, OI utilizes its resources 

by actively coordinating with the Department of Justice and other Federal, State, and local 

law enforcement authorities. The investigative efforts of OI often lead to criminal 

convictions, administrative sanctions, and/or civil monetary penalties. 

Office of Counsel to the Inspector General 

The Office of Counsel to the Inspector General (OCIG) provides general legal services to 

OIG, rendering advice and opinions on HHS programs and operations and providing all 

legal support for OIG’s internal operations. OCIG represents OIG in all civil and 

administrative fraud and abuse cases involving HHS programs, including False Claims Act, 

program exclusion, and civil monetary penalty cases. In connection with these cases, OCIG 

also negotiates and monitors corporate integrity agreements. OCIG renders advisory 

opinions, issues compliance program guidance, publishes fraud alerts, and provides other 

guidance to the health care industry concerning the anti-kickback statute and other OIG 

enforcement authorities. 
 

 

Δ EXECUTIVE SUMMARY 

OBJECTIVES 

1.	 To determine the extent to which Medicare Part B payments for 

facet joint injections meet Medicare program requirements. 

2.	 To determine what policies and safeguards exist to ensure that 

Medicare Part B payments for facet joint injections meet Medicare 

program requirements. 

BACKGROUND 

Medicare Part B payments for facet joint injections have increased from 

$141 million in 2003 to $307 million in 2006. Over the same period, the 

number of Medicare claims for facet joint injections increased by 

76 percent. 

Facet joints are joints in the spine that aid stability and allow the spine 

to bend and twist. Facet joint injections are a type of interventional 

pain management technique used to diagnose or treat back pain. Two 

primary codes, 64470 and 64475, are used to bill a single injection in the 

cervical/thoracic or lumbar/sacral areas of the spine, respectively. Each 

primary code has an associated add-on code for use when injections are 

provided at multiple spinal levels. Unilateral injections are performed 

on one side of the joint level, while bilateral injections are performed on 

the right and left side of the joint level. The Centers for Medicare & 

Medicaid Services (CMS) requires physicians to indicate a bilateral 

injection by using billing modifier 50. Physicians typically perform facet 

joint injections using radiological guidance to ensure correct needle 

placement and avoid nerve or other injury. Medicare Part B carriers 

are responsible for implementing program safeguards for these services. 

We conducted a medical record review of a stratified random sample of 

646 facet joint injection services performed in 2006. In addition, we 

interviewed staff from the 15 carriers that processed Medicare Part B 

claims in 2006 and reviewed their program safeguards for facet joint 

injections. 

FINDINGS 

Sixty-three percent of facet joint injection services allowed by 

Medicare in 2006 did not meet Medicare program requirements, 

resulting in approximately $96 million in improper payments. 

Medicare allowed an additional $33 million in improper payments for 

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EXECUTIVE SUMMARY 

associated facility claims. Thirty-eight percent of facet joint injection 

services had a documentation error and 31 percent had a coding error. 

For services that had a coding error, just over 60 percent were overpaid 

because physicians incorrectly billed additional add-on codes to 

represent bilateral facet joint injections instead of using modifier 50. 

Eight percent of services had a medical necessity error. Fourteen 

percent of services had one or more overlapping errors. 

Facet joint injection services provided in an office were more likely to 

have an error than those provided in an ambulatory surgical center or 

hospital outpatient department. 

In 2006, most carriers had policies and safeguards for facet joint 

injection services but they identified limits to using these 

safeguards. Local coverage determinations (LCD) and claims 

processing edits are carriers’ primary tools to protect Medicare 

payments for facet joint injections. Thirteen of fifteen carriers had 

LCDs for facet joint injections. Of carriers with LCDs, 10 had at least 

one active edit. 

Carrier staff identified two complexities in creating frequency limits for 

facet joint injections. First, the lack of consensus in the medical 

community about appropriate frequency of injections is a barrier to 

creating frequency limits in LCDs. Second, frequency edits for facet 

joint injections are difficult to automate because many require 

information that is not currently available on Medicare claims. 

RECOMMENDATIONS 

Based on the results of our review, CMS should: 

Strengthen program safeguards to prevent improper payment for 

facet joint injection services. CMS should assist carriers in developing 

ways to scrutinize physician claims for facet joint injection services 

provided in an office setting. CMS should also encourage carriers that 

require radiographic imaging guidance in their LCDs to implement 

automated edits for imaging guidance. Finally, CMS should direct 

carriers to revisit frequency limits in their LCDs and update them so 

that they are as effective as possible. 

Clarify billing instructions for bilateral services. CMS should clarify 

billing instructions for bilateral services and recover funds if 

appropriate. Correct use of add-on codes and modifier 50 could result in 

cost savings. 

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EXECUTIVE SUMMARY 

Take appropriate action regarding the undocumented, medically 

unnecessary, and miscoded services identified in our sample. We 

have forwarded information on these services to CMS. 

AGENCY COMMENTS AND OFFICE OF INSPECTOR GENERAL 

RESPONSE 

CMS described steps that it will take to address our recommendation to 

strengthen program safeguards for facet joint injection services. CMS 

agreed with our recommendations to clarify billing instructions for 

bilateral services and to take appropriate action on services paid in 

error in our sample. 

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Δ TABLE OF CONTENTS 

EXECUTIVE SUMMARY ..................................... i 
 

INTRODUCTION ........................................... 1 
 

FINDINGS ................................................ 11 
 

Sixty-three percent of services did not meet requirements ...... 11 
 

Carriers had safeguards but identified limits to using them .... 15 
 

RECOMMENDATIONS ..................................... 19

 Agency Comments and Office of Inspector General Response . . . 20 

APPENDIXES ............................................. 22 
 

A: Detailed Methodology ................................ 22 
 

B: Confidence Intervals for Selected Estimates .............. 25 
 

C: Specialty Error Rate in an Office Setting for Sample ....... 27 
 

D: Agency Comments ................................... 28 
 

ACKNOWLEDGMENTS .................................... 31 
 
 

 

 

Δ INTRODUCTION 

OBJECTIVES 

1.	 To determine the extent to which Medicare Part B payments for 

facet joint injections meet Medicare program requirements. 

2.	 To determine what policies and safeguards exist to ensure that 

Medicare Part B payments for facet joint injections meet Medicare 

program requirements. 

BACKGROUND 

According to one source, chronic pain affects more adults in the United 

States than diabetes, heart disease, and cancer combined.1 Treatment 

varies depending on the type of pain and can range from noninvasive to 

invasive procedures. Medicare paid over $2 billion in 2006 for 

interventional pain management procedures.2 Examples of 

interventional pain management procedures include: injections, nerve 

blocks, and spinal cord stimulation. 

From 2003 to 2006, the number of Medicare claims for facet joint 

injections, an interventional pain management procedure, increased by 

76 percent.3 Overall, payments for facet joint injections increased from 

$141 million in 2003 to $307 million in 2006.4 These payments 

represent both physician and facility payments. They account for 

approximately 15 percent of Medicare payments for interventional pain 

management services in 2006. 

In addition to an increase in Medicare payments, a number of recent 

investigations by the Federal Bureau of Investigations (FBI) and the 

Office of Inspector General (OIG) have found inappropriate activity 

related to facet joint injections and other types of pain management. In 

one joint FBI-OIG case, an Ohio physician was convicted of multiple 

1 American Pain Foundation. “Pain Facts & Figures.” (2007). Available online at 

http://www.painfoundation.org/page.asp?file=Newsroom/PainFacts.htm. Accessed on 

May 3, 2007. 

2 Estimate based on OIG analysis of interventional pain management procedure codes in 

the 2006 100-percent National Claims History (NCH) outpatient and physician/supplier 

files. 

3 Estimate based on OIG analysis of facet joint injection procedure codes in the following 

Medicare claims files: (1) 2003 1-percent sample of NCH outpatient and physician/supplier 

files, and (2) 2006 100-percent NCH outpatient and physician/supplier files. 

4 Ibid. 

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INTRODUCTION 
 

counts of health care fraud for interventional pain management 

procedures, including facet joint injections.5 

Facet Joint Injections 

Facet joints are joints in the spine that aid stability and allow the spine 

to bend and twist. Facet joints are located between each vertebra in the 

spinal column. See Figure 1 for an illustration of cervical facet joints. 

There are 25 levels of facet joints in the spine that are divided, from top 

to bottom, into cervical, thoracic, lumbar, and sacral regions.6 Each 

level has a pair of facet joints, one facet joint on the right and one on the 

left side of the spine. 

Figure 1. Cervical Facet Joints 

Source: The Pain Clinic. Available online at 

www.painclinic.org. Accessed on October 9, 2007. 

Facet joint injections are a type of interventional technique used to 

diagnose or treat back pain. For some people with chronic pain due to a 

facet joint injury, injections of an anesthetic or steroid into a facet joint 

5 U.S. Department of Justice, U.S. Attorney’s Office, Northern District of Ohio 

(June 9, 2006). Press release. Available online at 

http://www.usdoj.gov/usao/ohn/news/09June2006_2.html. Accessed on March 18, 2008. 

6 The Pain Clinic. “Facet Joint Injections.” (n.d.) Available online at 

http://www.painclinic.org/treatment-facetjointinjections.htm. Accessed on March 19, 2008. 

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INTRODUCTION 
 

help reduce inflammation and relieve pain. Figure 1 shows a unilateral, 

single-level injection into the C5-C6 facet joint level. Unilateral 

injections are performed on one side of the joint level, while bilateral 

injections are performed on the right and left side of the joint level. 

Frequency of injections. The frequency of facet joint injections varies for 

diagnostic and therapeutic injections. For a diagnostic injection, a 

physician injects a numbing medicine and/or a steroid into one or two 

suspect facet joints.7 The amount of immediate relief experienced by a 

patient will help confirm or reject the joint as the source of pain. For a 

therapeutic injection, a physician injects a numbing medicine and/or a 

steroid into one or more facet joints to reduce inflammation.8 Typically, 

a physician performs a diagnostic injection once, whereas therapeutic 

injections might be performed repeatedly for ongoing pain relief. 

Radiographic guidance. Facet joint injections are typically performed 

using radiological guidance (radiographic guidance or live x-ray) to 

ensure correct needle placement and avoid nerve or other injury. 

Sometimes, a physician performs the procedure without radiological 

imaging, which is referred to as a “blind” injection. One study of these 

“blind” injections concluded that facet joint injections should not be 

performed without the aid of radiological imaging because of potential 

risk to the patient and lack of diagnostic accuracy.9 

Setting and specialty. Facet joint injections may be performed in a 

variety of settings. In 2006, approximately 60 percent of facet joint 

injections were performed in an office setting, 20 percent in an 

ambulatory surgical center (ASC), and 20 percent in a hospital 

outpatient setting.10 In 2006, over 220,000 Medicare beneficiaries 

received a facet joint injection in one of these three settings.11 

Different physician specialties perform facet joint injections. In 2006, 

anesthesiologists, pain management specialists, and physiatrists 

7 M. Boswell, et al. (2007). “A Systematic Review of Therapeutic Facet Joint 

Interventions in Chronic Spinal Pain.” Pain Physician, 10, pp. 229–253. 

8 Ibid. 

9 G. Purcell-Jones, et al. (1989). “Paravertebral Somatic Nerve Block: A Clinical, 

Radiographic, and Computed Tomographic Study in Chronic Pain Patients.” Anesthesia & 

Analgesia, 68(1), 32-9. 

10 Estimate based on OIG analysis of facet joint injection procedure codes in the 2006 

NCH Medicare Part B physician/supplier file for amounts greater than $15 for ASC, office, 

and hospital outpatient department. 

11 Ibid. 

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INTRODUCTION 

performed approximately 64 percent of Medicare facet joint injections, 

while general practitioners, internal medicine physicians, and family 

practice physicians performed 19 percent. Other types of physicians 

performed the remaining 16 percent, including orthopedic surgeons, 

neurologists, and rheumatologists.12 

Medicare Program Requirements for Facet Joint Injections 

General provisions of the Social Security Act (the Act) govern Medicare 

reimbursement for all services, including facet joint injections. Section 

1862(a)(1)(A) of the Act states that Medicare will cover only services 

considered to be reasonable and necessary.13 Reasonable and necessary 

items are those used in the diagnosis or treatment of illness or to 

improve the functioning of a malformed body part. Further, section 

1833(e) of the Act states that payment is made only when a provider has 

furnished appropriate information about the service for the processing 

of the claim.14 

Medicare requires that providers report services using uniform 

procedure codes.15 The Current Procedural Terminology (CPT) codes 

and descriptions for facet joint injections are listed in Table 1. Two 

primary codes, 64470 and 64475, are used for a single injection in the 

cervical/thoracic or lumbar/sacral areas of the spine, respectively. Each 

primary code has an associated add-on code for use when more than one 

injection is provided in an area. The add-on codes are 64472 

(cervical/thoracic) and 64476 (lumbar/sacral). 

Table 1: Facet Joint Injection CPT Codes and Descriptions 

CPT Code Description 

64470 Injection; Paravertebral facet joint or facet joint nerve; cervical/thoracic, single level 

64472 (add-on) Injection; Paravertebral facet joint or facet joint nerve; cervical/thoracic, each additional level 

64475 Injection; Paravertebral facet joint or facet joint nerve; lumbar/sacral, single level 

64476 (add-on) Injection; Paravertebral facet joint or facet joint nerve; lumbar/sacral, each additional level 

Source: American Medical Association CPT descriptions, 2006. 

 OEI-05-07-00200 

12 OIG analysis of 2006 NCH Medicare Part B facet joint injection claims. Total does not 

sum to 100 percent because of rounding. 

13 Social Security Act § 1862(a)(1)(A), 42 U.S.C. § 1395y. 

14 Social Security Act § 1833(e), 42 U.S.C. § 13951. 

15 Section 1848(c)(5) of the Act required the Secretary of the Department of Health and 

Human Services to develop a uniform coding system for all physician services. The 

American Medical Association’s CPT is a numeric coding system for physicians’ services. 

MEDICARE PAYMENTS FOR FACET J OINT I NJECTION S ERVICES 4 
 

 

 

 

INTRODUCTION 

The “National Correct Coding Initiative Policy Manual” for Medicare 

Services (NCCI manual) outlines national correct coding guidelines for 

CPT codes.16 The NCCI manual states that providers should use the 

CPT codes that most comprehensively describe the services performed. 

The only specific references to facet joint injection codes in the NCCI 

manual relate to management of acute postoperative care. No guidance 

exists for facet joint injection codes outside of postoperative care. 

The NCCI manual and the “Medicare Claims Processing Manual” 

require that physicians use modifiers to indicate when a service differs 

from the CPT definition. Modifiers are two-digit codes billed in 

conjunction with the CPT code. Up to two modifiers are allowed for 

each CPT code on a claim. 

Medicare Part B Payments for Facet Joint Injections 

Medicare reimburses physicians and facilities for facet joint injections 

according to the Medicare Physician Fee Schedule and Medicare Facility 

Payment Rates, respectively.17 

Physician payments. The Medicare Physician Fee Schedule includes two 

types of fees, based on setting: those paid to physicians for services 

rendered in nonfacilities, such as their offices; and those paid to 

physicians for services rendered in facilities, such as ASCs and hospital 

outpatient departments. Physician fee schedule payments for office 

services are generally higher than physician fee schedule payments for 

facility services because they include payment for practice expenses 

such as building costs, salaries, and equipment. Fee schedule amounts 

are adjusted to account for geographic location. The base physician fee 

schedule rates for facet joint injections in 2006 are listed in Table 2. 

Table 2: Medicare Physician Fee Schedule Base 

Rates, 2006 

CPT Code Office Facility 

64470 $349.04 $101.19 

64472 (add-on) $140.60 $64.80 

64475 $318.72 $81.10 

64476 (add-on) $120.51 $48.89 

Source: Medicare Physician Fee Schedule, 2006. 

16 Centers for Medicare & Medicaid Services (CMS) “NCCI Policy Manual for Part B 

Medicare Carriers,” Version 12.3, Introduction, pages viii–9 (October 1, 2006). 

17 Section 1848(a)(1) of the Act established the physician fee schedule as the basis for 

Medicare reimbursement for all physician services beginning in January 1992. 

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INTRODUCTION 

Reimbursements for primary codes 64470 and 64475 are higher because 

they include presurgical and postsurgical expenses related to the 

procedure that the add-on codes, 64472 and 64476, do not. 

Physician payments also vary based on modifiers billed with the CPT. 

For example, bilateral facet joint injections, which are performed on 

both the right and left side of a level, should be billed using 

modifier 50, which increases reimbursement to 150 percent of the base 

rate.18 If a physician performs multiple bilateral injections, modifier 

50 should accompany each facet joint injection CPT code. 

Facility payments. Medicare reimburses ASCs and hospital outpatient 

departments for their expenses separately from the payments made to 

physicians for rendering services in these settings. Medicare facility 

payment rates for ASCs and hospital outpatient departments are based 

on ASC payment groups and the outpatient prospective payment 

system, respectively. Facility payment rates are adjusted to account for 

geographic location. The base facility payment rates for facet joint 

injections in 2006 are listed in Table 3. 

Table 3: Medicare Facility Base Payment Rates, 

2006 

CPT Code ASC Hospital Outpatient 

64470 $333 $357.90 

64472 (add-on) $333 $321.42 

64475 $333 $357.90 

64476 (add-on) $333 $321.42 

Source: Ambulatory Surgical Center Approved Healthcare 

Common Procedural Coding System (HCPCS) Codes and Payment 

Rates, 2006, and Hospital Outpatient Prospective Payment Rates, 

2006. 

Claims Processing and Program Safeguards 

CMS contracts with private organizations, called carriers, to process 

and pay Medicare Part B claims. In 2006, CMS contracted with 

15 carriers to process Medicare Part B claims in the 50 States, the 

District of Columbia, and U.S. territories. 

Carriers are also responsible for implementing program safeguards to 

reduce payment errors. To accomplish this, carriers create local 

coverage determinations (LCD), issue instructional articles, and 

18 CMS “Medicare Claims Processing Manual,” Pub. No. 100-04, ch. 12, § 40.7. 

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INTRODUCTION 
 

 OEI-05-07-00200 

implement claims processing edits. Carriers also analyze data, conduct 

provider education, and conduct medical reviews. 

Local coverage determinations. Because no National Coverage 

Determination19 exists for facet joint injections, carriers may develop 

their own local coverage guidelines called LCDs. The LCDs describe 

whether services are reasonable and necessary and therefore covered by 

Medicare. They also provide additional guidance to physicians about 

specific services. 

The LCDs vary by carrier and may result in different coverage in 

different parts of the country. They generally cover the following topics: 

• indications and limitations of coverage and medical necessity, 

• covered diagnosis codes supporting medical necessity, 

• documentation requirements, and 

• utilization guidelines. 

Claims processing edits. Carriers may implement automated electronic 

edits to prevent improper payments.20 These edits are coded system 

logic that automatically pay all or part of a claim, deny all or part of a 

claim, or suspend all or part of the claim for manual review. Carriers 

must have an LCD to implement their own local edits. 

CMS requires carriers to evaluate local prepayment edits annually for 

effectiveness. CMS considers an edit effective when it has a reasonable 

rate of denial relative to suspensions, a reasonable dollar return on the 

cost of operation, or potential to avoid significant risk to beneficiaries. 

Carriers also implement CMS-wide edits where appropriate. In 2007, 

CMS implemented Medically Unlikely Edits (MUE). CMS created 

MUEs to reduce the Medicare fee-for-service paid claims error rate.21 

Carriers deny the entire service when the billed units of service exceed 

MUE criteria.22 CMS bases the MUE criteria on data for past periods, 

clinical judgment of CMS health care professionals, and comments from 

19 National Coverage Determinations, issued by CMS, govern how Medicare will cover 

specific services, procedures, or technologies at a national level. 

20 CMS “Medicare Program Integrity Manual,” Pub. No. 100-08, ch. 3, § 3.5. 

21 CMS “Medicare Claims Processing Manual,” Pub. 100-04, Quarterly Update to 

Medically Unlikely Edits, Version 2.1, transmittal 1265. 

22 Ibid. 

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INTRODUCTION 

the health care community.23 Currently, CMS has an active MUE for 

facet joint injection services establishing an upper limit for the number 

of services a physician can bill.24 

METHODOLOGY 

To determine the extent to which facet joint injection services meet 

Medicare requirements, we: (1) conducted a medical record and coding 

review of a stratified random sample of allowed physician claims for 

Medicare Part B facet joint injection services in 2006, (2) reviewed CMS 

and carrier policies, and (3) conducted structured telephone interviews 

with carrier staff. 

Sample Selection 

The population from which we sampled consisted of all allowed 

physician services in the CMS NCH file for CPT codes 64470, 64472, 

64475, and 64476 performed in 2006. We excluded services with 

allowed amounts less than $15 to avoid performing a medical record 

review on low dollar claims.25 The population consisted of 

approximately 1 million services and $203 million in allowed physician 

payments. From this population, we selected a random sample of 

660 physician line item claims26 stratified by place of service and 

Medicare-allowed amount. See Appendix A for further detail on the 

sample selection, data collection, and data analysis. 

Data Collection 

After excluding 6 services from the 660 in our sample because of 

ongoing investigations by OIG, we requested, by mail, complete medical 

records from physicians for 654 sampled services. We classified 

providers for eight services as nonresponders.27 Thus, we based our 

review on the remaining 646 line items. This represents a 99-percent 

response rate. 

23 CMS MUE Project. Available online at 

http://www.cms.hhs.gov/MedicalReviewProcess/Downloads/MUECHARTER.pdf. Accessed 

on February 20, 2008. 

24 To protect MUE effectiveness, CMS prohibits specific MUE limits from being 

published. 

25 These services represent less than 1 percent of the population. 

26 Multiple line items may be billed on a single claim. Hereinafter, line items will be 

referred to as services. 

27 A nonresponder is defined as a provider with whom no successful contact has been 

made after at least three written contacts and two phone calls. 

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INTRODUCTION 
 

We also reviewed 15 carrier LCDs for facet joint injections. We then 

conducted 15 structured telephone interviews with carrier staff 

regarding policies and safeguards for facet joint injection services. We 

conducted one interview per carrier with the carrier medical director 

and support staff. We conducted these interviews between October and 

December 2007. 

Medical record review. We used a contractor to conduct the medical 

record review. The reviewers included five board-certified physicians 

with pain management and facet joint injection experience and one 

certified professional coder. One physician and the coder reviewed each 

of the medical records. The physician determined whether the service 

was adequately documented and medically necessary, while the coder 

determined the appropriate CPT code and modifier(s) for the service. 

Data Analysis 

We analyzed the results from the medical record review to determine 

the percentage of physician services that did not meet Medicare 

program requirements. We also calculated the projected physician 

dollars paid in error for these services. We then compared physician 

office error rates to facility (ASC and hospital outpatient) error rates. 

For our facility error rate, we combined ASC and hospital outpatient 

services, hereinafter referred to as facility. We did not compare ASC 

and hospital outpatient separately due to small sample sizes. Finally, 

when possible, we used the NCH files containing ASC and hospital 

outpatient department facility payments to match to the associated 

physician service. We projected the identified facility dollars paid in 

error. 

We analyzed all carrier interviews and classified their responses. In 

particular, we counted the number and type of edits each carrier had in 

place in 2006. We also noted common themes in the interviews. Finally, 

we reviewed all carrier LCDs for facet joint injections and assessed their 

similarities and differences. 

Comprehensive Error Rate Testing 

CMS established the Comprehensive Error Rate Testing (CERT) to 

calculate the Medicare fee-for-service paid claims error rate. As of 2007, 

the CERT has not reported any specific information about facet joint 

injection services. This review was not designed to reproduce or to review 

CERT findings. 

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INTRODUCTION 

Limitations 

Because we did not stratify our sample by carrier, we were not able to 

calculate medical review error rates by carrier. Therefore, we were 

unable to assess whether carrier program safeguards had an impact on 

error rates. 

Standards 

Our review was conducted in accordance with the “Quality Standards 

for Inspections” issued by the President’s Council on Integrity and 

Efficiency and the Executive Council on Integrity and Efficiency. 

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— 

 

Δ FINDINGS 

Sixty-three percent of facet joint injection services 

allowed by Medicare in 2006 did not meet 

Medicare program requirements, resulting in 

approximately $96 million in improper payments 

Medicare allowed approximately 

$96 million in improper payments 

to physicians for facet joint 

injection services in 2006. These 

improper payments represent 

47 percent of the $203 million physician payments for facet joint 

injections in 2006. 

Medicare allowed an additional $33 million in improper payments for 

associated facility claims. While the focus of this review is on physician 

claims, we also calculated facility claims that were submitted for the 

physician claims paid in error to provide additional context. The 

remaining analysis focuses on physician claims only. 

Sixty-three percent of facet joint injection services did not meet 

Medicare requirements. Table 4 provides a breakdown of error rates 

and associated payments for physician claims by error type. Confidence 

intervals for projected error rates and payments are in Appendix B. 

Table 4: Improperly Paid Medicare Facet Joint Injection Services 

Physician Claims, 2006 

Type of Error 

Sample Projected 

Services Allowed 

Amount Services Allowed Amount 

Documentation 

Coding 

Medical Necessity 

196 

173 

43 

$35, 835 

$11,670 

$7,394 

38% 

31% 

8% 

$81 million 

$21 million 

$17 million 

(Overlapping Errors) (71) ($12,247) (14%) ($23 million) 

Total 341 $42,651* 63% $96 million 

Source: OIG analysis of medical review results, 2008. 

* Numbers do not sum to total because of rounding. 

Thirty-eight percent of facet joint injection services had a documentation 

error 

Medicare allowed approximately $81 million for physician services that 

were either undocumented or insufficiently documented. Although 

some cases of missing documentation may be due to errors, others may 

represent services not rendered. Claims for services that lack sufficient 

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FINDINGS 

documentation to show that care was provided do not meet Medicare 

program requirements.28 

Twenty-seven percent of facet joint injection services were undocumented. 

Medicare allowed approximately $59 million for undocumented facet 

joint injection services. For the majority of these services, physicians 

submitted no medical records for the sampled services. For the 

remaining services, a record was submitted but contained no 

documentation of the sampled services. 

Eleven percent of facet joint injection services were insufficiently 

documented. Medicare allowed approximately $22 million for 

insufficiently documented facet joint injections. The majority of records 

for these services were missing a description of the procedure that was 

billed. Others had a procedure note, but were missing details of the 

procedure, such as which levels and sides of the back were injected. In 

each case, the physician reviewer concluded there was insufficient 

documentation to support the service. 

Thirty-one percent of facet joint injection services had a coding error 

Medicare allowed approximately $21 million in overpayments, net of 

underpayments, to physicians for facet injection services that physicians 

billed with codes that did not accurately reflect the service described in 

the medical record. Approximately 79 percent of miscoded services 

affected payment; 82 percent were overpayments and 18 percent were 

underpayments. See Appendix B for the dollars associated with 

overpayments and underpayments. 

Just over 60 percent of the overpaid services were instances in which the 

physician billed incorrectly for bilateral facet joint injections. Of the 

miscoded services that were overpaid, 61 percent were instances in 

which the physician incorrectly billed CPT add-on codes to represent 

bilateral facet joint injections instead of using modifier 50. Specifically, 

they billed multiple lines of CPT add-on codes 64472 or 64476 in 

addition to a primary code. Physicians should use add-on codes to 

represent additional levels of the back injected, not sides. As previously 

noted, the NCCI manual and “Medicare Claims Processing Manual” 

require that physicians use modifiers to indicate when they are billing 

for bilateral facet joint injection services. For example, a physician 

billing two add-on codes to represent a bilateral service receives 

28 Social Security Act § 1833(e); 42 U.S.C. § 13951(e). 

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FINDINGS 

200 percent of the base payment when he or she should receive 

150 percent of the base payment. Billing add-on codes to represent 

bilateral injections results in a 50-percent higher net payment than 

Medicare should have allowed. 

Physicians may have accidentally billed some of these miscoded services 

because of confusion about appropriate coding rules. Other miscoded 

services may have been intentionally exploited for higher payment. 

Additional investigation would be needed to distinguish accidental 

errors from potentially fraudulent activity. 

All of the underpayments in our sample were for bilateral facet joint 

injections for which the provider only billed for unilateral services. All 

29 of the underpaid services in our sample were bilateral facet joint 

injections for which the provider billed only for unilateral services, 

resulting in a 50-percent underpayment.29 

Eight percent of facet joint injection services had a medical necessity error 

Medicare allowed approximately $17 million to physicians for facet joint 

injection services that medical reviewers determined were medically 

unnecessary. In many instances, reviewers indicated that the record 

did not contain any patient history or physical exam to show that the 

treatment was medically indicated for the patient. In other instances, 

reviewers noted that the record was missing imaging studies to support 

the diagnosis and justify facet joint injections as the treatment. 

Facet joint injection services provided in an office were more likely to have 

an error than those provided in a facility 

Seventy-one percent of facet joint injection services provided in an office 

had some type of error, compared to 51 percent of facet joint injection 

services provided in a facility. See Table 5 on the following page for 

error rates by setting and error type. 

29 Statement is based only on the sample and not on a projection to the population. 

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FINDINGS 

Table 5: Error Rate by Setting and Error Type for Medicare 

Facet Joint Injection Services—Physician Claims, 2006 

Type of Error Office Facility 

Documentation* 

Coding 

Medical Necessity 

49% 

30% 

10% 

22% 

32% 

5% 

Any Error* 71%** 51% 

Source: OIG analysis of medical review results, 2008. 

* Statistically significant at the 95-percent confidence level.
 

** Numbers do not sum to total because of overlapping errors. 

In addition, certain physician specialties in our sample had high error 

rates in an office setting.30 See Table 6 for physician specialty error 

rates in an office setting for our sample. For a complete list of specialty 

error rates in an office setting for our sample, see Appendix C. 

Table 6: Physician Specialty Error Rate in an Office Setting for Sample 

Specialty** 

Specialty 

Code Any Error in Office* Services in Office* 

Percentage of 

Services With 

an Error 

in Office 

General Practice 01 36 37 97% 

Internal Medicine 11 13 15 87% 

Family Practice 08 7 9 78% 

Neurology 13 8 11 73% 

Rheumatology 66 5 7 71% 

Orthopedic Surgery 20 9 14 64% 

Anesthesiology 05 30 48 63% 

Pain Management 72 14 25 56% 

Physical Medicine and 

Rehabilitation 

25 8 15 53% 

Source: OIG analysis of medical review results, 2008. 

* Figures are based only on the sample and are not projected to the population. 

** Only specialties with sample frequency equal to or greater than five are shown here. 

30 Statement is based only on the sample and not on projection to the population. 

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FINDINGS 

In 2006, most carriers had policies and 

safeguards for facet joint injection services but 

they identified limits to using these safeguards 

The LCDs and claims processing 

edits are carriers’ primary tools to 

protect Medicare payments for 

facet joint injections. Carrier 

staff, however, identified limits to 

using LCDs and edits to safeguard these services. Carrier staff reported 

minimal use of other safeguards for facet joint injections. 

Almost all carriers had an LCD and at least one edit for facet joint injections 

In 2006, 13 of 15 carriers had LCDs for facet joint injections. Of carriers 

with an LCD, 10 had at least one active edit. Table 7 illustrates the 

safeguards each carrier had in 2006 for facet joint injection services. 

Table 7: Carrier Safeguards for Facet Joint Injection Services in 2006 

Carrier LCD 

Claims Processing Edits 

Edits for 

Diagnosis 

Edits for 

Frequency 

Edits for 

Radiographic 

Guidance Edits–Other 

1 U U 

2 

3 U U U U U 

4 U 

5 U U U 

6 U U 

7 U 

8 U U U U 

9 U U U 

10 U 

11 U U 

12 U U U 

13 U U U U 

14 U U U 

15 

 Total 13 10 4 1 6 

Source: OIG interviews and document review, 2007. 

Local coverage determinations. Specific guidelines in LCDs varied by 

carrier. For example, 13 carriers considered facet joint injections to be 

medically necessary for patients with certain diagnosis codes; however, 

the number of acceptable diagnosis codes varied by carrier from 3 to 38. 

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FINDINGS 

Despite the variation in acceptable diagnosis codes, some commonalities 

in the guidelines exist. Seven of the LCDs describe radiographic 

guidance as part of the standard of care for facet joint injections and 

require that providers use radiographic guidance for this service. In 

addition, six of the LCDs restrict providers from performing other 

interventional pain management procedures in the same anatomical 

region on the same day as a facet joint injection. Eight LCDs include 

frequency guidelines for diagnostic and therapeutic facet joint 

injections. 

Claims processing edits. Ten carriers implemented automated 

electronic edits to enforce the guidelines established by their LCDs. 

Carriers most commonly used the diagnosis edit, which automatically 

checks to ensure that physicians bill an acceptable diagnosis code for 

facet joint injections. Four carriers used frequency edits, which deny or 

flag claims that exceed a limit for facet joint injections established by 

the LCD. 

While half of the carriers require the use of radiographic guidance in 

their LCD, only one carrier in 2006 used an imaging edit to auto-deny 

facet joint injection claims billed without radiographic guidance. 

Carrier staff stated that the edit for radiographic guidance addresses 

two potential problems: (1) a facet joint injection billed without 

radiographic guidance indicates that it was not performed with 

guidance, which could put the patient at risk; and (2) without 

radiographic guidance, the procedure might have been a trigger point 

injection, a lower paying pain management service. 

Several carriers also created unique claims processing edits. For 

example, one carrier created an edit to deny any facet joint injection 

service billed on the same day as another pain management service. 

Another carrier created an edit that automatically suspends all claims 

with add-on facet joint injection codes for manual review because of an 

identified issue with add-on codes being billed to represent bilateral 

services. 

Other safeguards. Carrier staff did not report frequent use of other 

safeguards for facet joint injections, such as provider education and 

medical review. Carriers reported that their routine data analysis did 

not identify specific outliers in the data for these services. As a result, 

only three carriers conducted provider education and medical reviews 

for facet joint injections. 

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FINDINGS 

Carrier staff identified complexities to creating frequency limits for facet 

joint injections 

Generally, carriers use LCDs and edits to protect the integrity of 

Medicare payments and control utilization for vulnerable services. 

Establishing frequency limits in LCDs and corresponding edits to 

enforce those limits is a common technique. However, carrier staff 

identified complexities that make frequency limits harder to implement 

for facet joint injections. 

Staff at two-thirds of carriers identified barriers to implementing 

frequency limits for facet joint injections. First, one-third identified the 

lack of agreement in the medical community about appropriate 

frequency for facet joint injections as a barrier to creating LCDs. An 

additional one-third mentioned difficulty creating automated edits for 

facet joint injections. 

Lack of consensus about appropriate frequency is a barrier to creating 

frequency limits in local coverage determinations. Carriers rely on clinical 

standards in the medical community to support specific guidelines in 

LCDs. However, the medical community has not yet established a body 

of evidence-based medicine to support frequency standards for facet 

joint injections. In the absence of clear standards in the medical 

community, carriers must search for consensus among physicians who 

perform the services. Reaching consensus is often challenging given 

that many different provider specialties perform facet joint injections 

and have varying opinions about the appropriate frequency. 

Four carriers have successfully reached consensus on frequency limits 

and enforce those limits with automated edits. Staff at one carrier, 

however, reported that the limits were too high to identify potential 

problems. 

Frequency edits for facet joint injections are difficult to automate. Carrier 

staff report that even if they were able to establish frequency limits in 

their LCD, automated prepay frequency edits are inherently difficult for 

facet joint injections. Many of the automated edits require information 

that is not currently available on Medicare claims. 

Specifically, carriers are not able to establish frequency edits that rely 

on spinal level. Currently, the CPT and the claim do not distinguish 

spinal level. The CPT code indicates what region of the spine is 

injected, such as lumbar/sacral. However, the CPT code does not 

indicate which spinal level within that region was injected (such as 

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FINDINGS 

C5-C6). Without this information on the claim, carriers cannot create 

specific frequency edits based on spinal level. 

Claims do not have enough information for carriers to distinguish a 

diagnostic injection from a therapeutic injection, which affects the 

accuracy of frequency edits. Physicians generally do not perform 

diagnostic injections more than once, while therapeutic injections may 

be repeated multiple times. Even with a specific frequency standard in 

an LCD for each, carriers would have difficulty editing for these services 

because claims do not indicate whether the service is being performed 

for diagnostic or therapeutic purposes. 

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Δ RECOMMENDATIONS 

Sixty-three percent of Medicare facet joint injection services in 2006 did 

not meet program requirements, resulting in approximately $96 million 

in improper payments to physicians and $33 million to facilities. 

Although carriers have LCDs and claims processing edits for these 

services, they will likely continue to experience problems safeguarding 

these services until there is a comprehensive body of medical evidence 

and consensus in the medical community about facet joint injections. 

Based on the results of our review, CMS should: 

Strengthen Program Safeguards To Prevent Improper Payment for Facet 

Joint Injection Services 

To strengthen program safeguards, CMS could: 

Assist carriers in developing ways to scrutinize claims for facet joint injection 

services provided in an office setting. As error rates were significantly higher 

in an office setting than a facility, carriers may be able to identify 

problematic claims by examining place of service. 

Encourage carriers that require radiographic imaging guidance in their LCDs to 

implement automated edits for imaging guidance. Carriers that require 

radiographic imaging in their LCDs should implement automated edits for 

imaging guidance if they have not already done so. The edit would autodeny any facet joint injection claim submitted without imaging guidance 

by checking for the procedure code(s) associated with radiographic imaging 

guidance. 

Direct carriers to revisit frequency limits in their LCDs for facet joint injections. 

Carriers should revisit the frequency limits in their LCDs and update 

them so that they are as effective as possible. Carriers that currently have 

frequency edits for facet joint injections could revisit quarterly claims data 

to determine edit effectiveness. 

CMS bases current MUE limits for facet joint injections on previous billing 

patterns, which could be inflated because of inappropriate payments. 

These limits are not sufficient to identify inappropriate claims for facet 

joint injections. 

Clarify Billing Instructions for Bilateral Services 

CMS should clarify billing instructions for bilateral services and recover 

funds if appropriate. CMS should address the fact that some providers 

obtain higher reimbursement than allowed by billing add-on codes to 

represent bilateral service. CMS could accomplish this through a 

variety of mechanisms: educating providers, issuing program 

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RECOMMENDATIONS 

memorandums, and encouraging carriers to flag add-on codes for 

additional review. Correct billing for bilateral services could result in 

cost savings. 

Take Appropriate Action Regarding the Undocumented, Medically 

Unnecessary, and Miscoded Services Identified in Our Sample 

We have forwarded information on these services to CMS. 

AGENCY COMMENTS AND OFFICE OF INSPECTOR GENERAL 

RESPONSE 

CMS described steps that it will take to address our recommendation to 

strengthen program safeguards for facet joint injection services. CMS 

agreed with our recommendations to clarify billing instructions for 

bilateral services and to take appropriate action on services paid in 

error in our sample. 

To strengthen program safeguards for facet joint injections, CMS plans 

to direct carriers to review claims data, particularly for services 

performed in office settings, and establish additional safeguards as 

necessary. CMS also plans to encourage carriers to consider automated 

edits for radiographic imaging where it is already required in their 

LCD. Finally, CMS expects that frequency limits will be addressed by 

the annual review of LCDs and by the Medicare Administrative 

Contractors (MAC) during contract consolidation. 

We continue to recommend that CMS instruct MACs and remaining 

carriers specifically to revisit frequency limits for facet joint injections 

during annual reviews or during MAC consolidation. Without specific 

instruction by CMS, carrier annual reviews and MAC consolidation 

might not address the frequency recommendation in this report. 

Further, MAC reconciliation of LCDs could lead to less restrictive 

frequency limits. CMS comments describe how MACs reconcile varying 

frequency limits in LCDs and follow either the most clinically 

appropriate or the least restrictive requirement. However, without 

medical community consensus on the clinically appropriate frequency 

for facet joint injections, MACs may default to the least restrictive 

requirement which, in some cases, could be no limit. At the time of our 

study, 7 of 15 carriers did not have frequency limits in their LCDs. 

To clarify billing instructions for bilateral services, CMS will issue a 

Medicare Learning Network Matters article to educate providers on the 

proper use of add-on codes and the bilateral modifier. 

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RECOMMENDATIONS 

To address the services paid in error in our sample, CMS will review the 

claims data and direct Medicare contractors to review the claims and 

initiate appropriate recoveries of potential overpayments. 

For the full text of CMS’s comments, see Appendix D. 

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Δ APPENDIX~A 

Detailed Methodology 

Sample Selection 

The population from which we sampled consisted of all the allowed 

physician services in the Centers for Medicare & Medicaid Services 

National Claims History (NCH) file for Current Procedural 

Terminology (CPT) codes 64470, 64472, 64475, and 64476 performed 

in 2006. We excluded services with allowed amounts less than 

$15 to avoid performing a medical record review on low-dollar 

claims.31 The population consisted of 1,072,841 services that 

represented $202,671,303 in allowed physician payments. We 

stratified the population based on place of service and 

Medicare-allowed amounts. The strata included services with low 

and high allowed amounts performed in physician offices, hospital 

outpatient departments, and ambulatory surgical centers (ASC). 

We took a stratified, simple random sample of 660 line items32 and 

excluded 6 services because of ongoing investigations by the Office of 

Inspector General (OIG). Our final sample included a total of 654 

services. Table 8 shows the six strata and the number of services in 

each stratum. 

Table 8: Population Count and Sample Size by Strata 

Number of 

Number of Services in Services in 

Stratum Medicare-Allowed Amount Population Sample 

1 – Office Greater than $300 242,806 108 

2 – Office Greater than $15 and less 

than or equal to $300 412,213 108 

3 – Hospital Outpatient Greater than $100 50,916 109 

4 – Hospital Outpatient Greater than $15 and less 

than or equal to $100 170,891 110 

5 – ASC Greater than $100 48,653 110 

6 – ASC Greater than $15 and less 

than or equal to $100 147,362 109 

Total 1,072,841 654 

Source: OIG sample stratification, 2008. 

31 These services represent less than 1 percent of the population. 

32 Hereinafter, line items will be referred to as services. 

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APP E N D I X ~A 

Data Collection 

We used a contractor to conduct the medical record request and 

review. We requested, by mail, complete medical records and 

documentation from physicians for each of the 654 sampled services. 

We specified that physicians should include the following when 

available: initial patient evaluation and exam, test results, 

radiographic evidence of needle placement, and procedure notes. For 

additional context, we also requested that physicians furnish all 

documentation for services provided to the beneficiary 4 months 

before and 1 month after the sampled date of service. 

We classified physicians for eight services as nonresponders. A 

nonresponder is a provider with whom no successful contact has been 

made after at least three written contacts and two phone calls. The 

final request letters were sent by certified mail. We based our review 

on the remaining 646 line items, corresponding to a 99-percent 

response rate. 

Test review. To test our review instrument and ensure uniformity 

among the reviewers, we conducted a preliminary medical review of 

12 services. These services were randomly sampled from the same 

population from which we drew our final sample using the same 

stratification.33 We analyzed the results of the test review and 

presented them to the reviewers. Reviewers resolved inconsistencies in 

the results and suggested changes to the review instrument. Some of 

these changes were incorporated into the final review instrument. 

Data Analysis 

Calculation of improper physician payments. We calculated the total actual 

and projected dollars paid in error for these services. For services that 

were not medically necessary, insufficiently documented, or not 

documented, we counted the entire Medicare-allowed amount as improper 

and projected the amount paid in error. For services with a coding error, 

we determined if the error was a Medicare underpayment, overpayment, 

or had no effect on payment. We calculated the total net difference for all 

services with a coding error and projected it to the population of facet joint 

injection services in 2006. The only overpayments and underpayments 

included in the projection are cases for which we could calculate the exact 

amount overpaid or underpaid. We were able to calculate the exact 

33 This sample was drawn separately from the sample used for our review. 

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APPENDIX~A 

amount overpaid or underpaid for 137 of the 173 miscoded services. We 

were unable to calculate exact amounts for 36 services. Of the 36 services, 

20 were for overpayments, 4 were for underpayments, and 12 were for 

services that had no effect or an unknown effect on payment. For services 

for which we could not determine the exact amount, we assumed there was 

no effect on payment. As a result, the projected overpayment is a 

conservative estimate. 

Calculation of improper facility payments. In addition, we calculated and 

projected the facility payments associated with the services that did not 

meet Medicare program requirements. For ASC and outpatient claims, we 

used the NCH Part B file and hospital outpatient file, respectively, and 

matched facility claims to physician claims using the date of service, CPT, 

and beneficiary identification. We were able to match 88 percent of 

sampled services performed in a facility to their associated facility 

payments.34 Finally, we projected the facility dollars associated with 

physician services paid in error. 

34 We matched 384 of the 485 sampled services in a facility. We were not able to match 

the remaining facility payments to physician payments for a number of reasons, including 

facilities failure to submit a service and incorrect coding of the place of service by the 

physician. 

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Δ APPENDIX~B 

Confidence Intervals for Selected Estimates 

Table 9: Estimates of All Errors 

Estimate Description Point Estimate 95-Percent Confidence Interval 

Percentage of services with any error 63.1% 59.0%–67.2% 

Percentage of services with any documentation error 38.4% 33.8%–42.9% 

Percentage of services with no documentation 27.5% 23.1%–31.8% 

Percentage of services with insufficient documentation 10.9% 7.8%–14.1% 

Percentage of services coded incorrectly 31.1% 26.7%–35.4% 

Percentage of services that were not medically necessary 8.1% 5.4%–10.9% 

Percentage of services with overlapping errors 14.0% 9.8%–18.2% 

Source: Office of Inspector General (OIG) analysis of medical review results, 2008. 

Table 10: Estimates of Improper Physician Payments Associated With All Errors 

Estimate Description Point Estimate 95-Percent Confidence Interval 

Amount allowed for services with any error $95,792,055 $84,298,604–$107,285,504 

Amount allowed for services with any documentation error $80,733,041 $69,246,854–$92,219,228 

Amount allowed for services with no documentation $58,587,140 $47,833,250–$69,341,030 

Amount allowed for services with insufficient documentation $22,145,901 $14,671,642–$29,620,160 

Amount allowed for services coded incorrectly $21,391,947 $13,902,518–$28,881,376 

Amount allowed for services that were not medically necessary $16,648,373 $9,919,301–$23,377,445 

Amount allowed for services with overlapping errors $22,981,307 $12,657,976–$33,304,637 

Source: OIG analysis of medical review results, 2008. 

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APPENDIX~B 

Table 11: Estimate of Improper Facility Payments Associated With Any Error 

Estimate Description Point Estimate 95-Percent Confidence Interval 

Amount allowed for services with any error $32,697,195 $26,899,820–$38,494,570 

Source: OIG analysis of medical review results, 2008. 

Table 12: Estimates of Miscoded Services 

Estimate Description Point Estimate 95-Percent Confidence Interval 

Percentage of miscoded services that affected payment 79.0% 71.8%–86.1% 

Percentage and amount allowed for services affecting payment 81.6% 74.6%–88.6% 

that were overpaid $25,063,648 $18,022,097–$32,105,198 

Percentage and amount allowed for services affecting payment 18.4% 11.4%–25.4% 

that were underpaid $3,671,701 $1,585,607–$5,757,794 

Percentage of overpaid services because of a bilateral billing 

error 61.2% 50.3%–72.1% 

Source: OIG analysis of medical review results, 2008. 

Point 

Error Type Setting Estimate 95-Percent Confidence Interval 

Office 49.1% 42.1%–56.1% 

Any Documentation Error 

Facility 22.2% 17.8%–26.7% 

Office 30.3% 23.8%–36.8% 

Coded Incorrectly 

Facility 32.2% 27.2%–37.3% 

Office 10.3% 5.9%–14.7% 

Not Medically Necessary 

Facility 4.9% 2.7%–7.2% 

Office 71.2% 65.4%–77.1% 

Any Error 

Facility 50.8% 45.5%–56.1% 

Table 13: Estimates of Errors and Improper Payments by Setting 

Source: OIG analysis of medical review results, 2008. 

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Δ APPENDIX~C 

Specialty Error Rate in an Office Setting for Sample 

Table 14: Physician Specialty Error Rate in an Office Setting for Sample 

Any Error in Office* Services in Office* 

Specialty 

Specialty 

Code 

Sample 

Frequency 

Sample 

Percentage 

Sample 

Frequency 

Sample 

Percentage 

Percentage of 

Services With an 

Error 

in Office 

Neurosurgery 14 3 2% 3 1% 100% 

General Surgery 02 1 1% 1 0% 100% 

Pathology 22 1 1% 1 0% 100% 

Nurse Practitioner 50 1 1% 1 0% 100% 

Emergency Room 93 1 1% 1 0% 100% 

Physician Assistant 97 1 1% 1 0% 100% 

General Practice 01 36 25% 37 18% 97% 

Internal Medicine 11 13 9% 15 7% 87% 

Family Practice 08 7 5% 9 4% 78% 

Neurology 13 8 6% 11 5% 73% 

Rheumatology 66 5 4% 7 3% 71% 

Pediatric Medicine 37 2 1% 3 1% 67% 

Orthopedic Surgery 20 9 6% 14 7% 64% 

Anesthesiology 05 30 21% 48 23% 63% 

Pain Management 72 14 10% 25 12% 56% 

Physical Medicine 

and Rehabilitation 

25 8 6% 15 7% 53% 

Interventional Pain 

Management 

09 2 1% 17 8% 12% 

Diagnostic 

Radiology 

30 0 0% 1 0% 0% 

Source: Office of Inspector General analysis of medical review results, 2008. 

* Figures are based only on the sample and are not projected to the population. 

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Agency Comments 

Δ APPENDIX~D 
 

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APPENDIX~D 
 

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APPENDIX~D 
 

Δ ACKNOWLEDGMENTS 

This report was prepared under the direction of Ann Maxwell, Regional 

Inspector General for Evaluation and Inspections in the Chicago 

regional office, and Thomas Komaniecki, Deputy Regional Inspector 

General. 

Laura Kordish served as the team leader for this study and Kelly 

Sullivan Waldhoff served as the lead analyst. Other principal Office of 

Evaluation and Inspections staff from the Chicago regional office who 

contributed to this report include Nicole Hrycyk; central office staff who 

contributed include Doris Jackson, Sandy Khoury, Megan Ruhnke, and 

Barbara Tedesco. 

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