Department of Health and Human Services 
OFFICE OF 
 
INSPECTOR GENERAL 
 
 
 
 
 
 
A E
DVERSE  VENTS IN 
 
 
R H :
EHABILITATION  OSPITALS   
 
 
N I A
ATIONAL  NCIDENCE  MONG 
M B  
EDICARE  ENEFICIARIES 
 
Daniel R. Levinson  
Inspector General 
 
July 2016 
OEI-06-14-00110   
EXECUTIVE SUMMARY:  ADVERSE EVENTS IN REHABILITATION HOSPITALS:  
NATIONAL INCIDENCE AMONG MEDICARE BENEFICIARIES 
OEI-06-14-00110 
 
WHY WE DID THIS STUDY  
This report is part of a series on adverse events in healthcare settings, defined as harm resulting 
from medical care.  Previous OIG work identified harm rates of about 30 percent in both acute-
care hospitals and skilled nursing facilities (SNF), with an attendant toll on patient health and 
taxpayers costs, the latter amounting to billions of dollars annually.  This report extends our 
work by evaluating care provided in rehabilitation (rehab) hospitals.  Rehab hospitals are post-
acute providers that specialize in intensive rehabilitative care for patients recovering from illness, 
injury, or surgery.  While in recent years stakeholders have paid considerable attention to patient 
safety in acute-care hospitals and increasingly in SNFs, less is known about adverse events in 
other health care settings.  An increased understanding of adverse events that occur in this unique 
setting would better equip health care providers and other stakeholders in taking actions to 
improve the safety of patient care in rehab hospitals.     
 
HOW WE DID THIS STUDY 
We reviewed medical records to estimate the national incidence rate, preventability, and costs of 
adverse events in rehab hospitals.  We reviewed a nationally representative sample of 
417 Medicare beneficiaries discharged from rehab hospitals in March 2012.   
 
WHAT WE FOUND 
An estimated 29 percent of Medicare beneficiaries experienced adverse or temporary harm 
events during their rehab hospital stays, resulting in temporary harm; prolonged stays or transfers 
to other hospitals; permanent harm; life-sustaining intervention; or death.  This harm rate is in 
line with what we found in hospitals (27 percent) and in SNFs (33 percent).  Physician reviewers 
determined that 46 percent of these adverse and temporary harm events were clearly or likely 
preventable.  Physicians attributed much of the preventable harm to substandard treatment, 
inadequate patient monitoring, and failure to provide needed treatment.  Nearly one-quarter of 
the patients who experienced adverse or temporary harm events were transferred to an acute-care 
hospital for treatment, with an estimated cost to Medicare of at least $7.7 million in one month, 
or at least $92 million in one year, assuming a constant rate of hospitalization throughout the 
year. 
 
WHAT WE RECOMMEND 
The incidence of adverse events in rehab hospitals is similar to that in acute-care hospitals and 
SNFs, as reflected in previous OIG findings, confirming the need and opportunity to 
significantly reduce the incidence of adverse events across health care settings.  We recommend 
that the Agency for Healthcare Research and Quality (AHRQ) and the Centers for Medicare & 
Medicaid Services (CMS) raise awareness of patient safety issues in rehab hospitals and seek to 
reduce patient harm.  This effort should include: (1) collaboration to create and disseminate a list 
of potential adverse events that occur in rehab hospitals and (2) the addition of information about 
potential adverse events in quality guidance to rehab hospitals.  CMS and AHRQ concurred with 
our recommendations.       
   
TABLE OF CONTENTS 
Objectives ....................................................................................................1 
Background ..................................................................................................1 
Methodology ................................................................................................4 
Findings........................................................................................................8 
An estimated 29 percent of Medicare patients in rehab hospitals 
experienced adverse or temporary harm events ...............................8 
Forty-six percent of adverse and temporary harm events                    
were preventable  ........................................................................... 11 
Nearly one-quarter of the Medicare patients who experienced an 
adverse or temporary harm event in a rehab hospital were 
transferred to an acute-care hospital for treatment ........................12 
Conclusion and Recommendations ............................................................14 
            Agency Comments and Office of Inspector General Response .....16 
Appendixes ................................................................................................17 
A:  Methodology for Identifying Events and Determining 
Preventability .................................................................................17 
B:  Triggers Listed on the Trigger Tool Worksheet........................21 
C:  Estimates, Confidence Intervals, and Key Statistics ................22 
D:  Rates of Adverse Events and Temporary Harm Events in     
Rehab Hospitals by Patient Days and by Admissions ...................24 
E:  Adverse Events and Temporary Harm Events Identified           
in the Sample..................................................................................25 
F:  Agency Comments ....................................................................32 
Acknowledgments......................................................................................35 
 
 
   
   
OBJECTIVES 
1.  To estimate the incidence of adverse and temporary harm events for 
Medicare beneficiaries admitted to rehabilitation (rehab) hospitals for 
post-acute care. 
2.  To assess the extent to which adverse and temporary harm events were 
preventable and identify contributing factors. 
3.  To estimate the extent and cost of acute-care hospital admissions and 
emergency department visits that resulted from adverse and temporary 
harm events.  
BACKGROUND  
Adverse Events in Health Care 
The term adverse event describes harm to a patient as a result of medical 
care, including the failure to provide needed care.1  An adverse event 
indicates that the care resulted in an undesirable clinical outcome not caused 
by underlying disease.  Adverse events include medical errors and general 
substandard care that result in patient harm, such as infections caused by the 
use of contaminated equipment.  However, adverse events do not always 
involve errors or poor quality of care and are not always preventable.2      
Office of Inspector General Reports on Adverse Events 
In a series of reports from 20082014, the Office of Inspector General 
(OIG) demonstrated that adverse events are common and costly to the 
Medicare program.3  In a 2010 study, OIG found that 27 percent of 
hospitalized Medicare beneficiaries experienced adverse or temporary 
harm events.4  Nearly half of the events were preventable, and care 
associated with events cost Medicare an estimated $4.4 billion a year.  
OIG also found that most hospital staff did not recognize or report patient 
harm when it occurred.5  In a 2014 study, OIG found that 33 percent of 
Medicare residents in post-acute Skilled Nursing Facility (SNF) stays 
____________________________________________________________ 
1 For the purposes of analysis in this report, we divide adverse events into two groups:  
adverse events and temporary harm events.  We define temporary harm events as events that 
harmed patients and required medical intervention but did not cause lasting harm.   
2 R. M. Wachter, Understanding Patient Safety, Second Edition, McGraw-Hill, 2012, p. 17.   
3 OIG issued 11 reports regarding adverse events from 20082014, including reports about 
the incidence of adverse events, methods for identifying adverse events, hospital incident 
reporting systems, and public disclosure of event information.  All reports are available at  
https://oig.hhs.gov/reports-and-publications/oei/a.asp#adverse_care.  
4 OIG, Adverse Events in Hospitals:  National Incidence Among Medicare Beneficiaries,  
OEI-06-09-00090, November 2010.   
5 OIG, Hospital Incident Reporting Systems Do Not Capture Most Patient Harm, 
OEI-06-09-00091, January 2012.   
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  1 
   
   
experienced adverse and temporary harm events.6  Over half (59 percent) 
of these SNF events were preventable, and care associated with these 
events cost Medicare an estimated $2.8 billion in a single year.   
Post-Acute Care in Rehab Hospitals 
Rehab hospitals are independently run inpatient facilities that specialize in 
providing intensive rehabilitation therapy to patients recovering from 
illness, injury, or surgery.7  Patients entering rehab hospitals must be able 
to tolerate and benefit from at least 3 hours of therapy a day, 5 days a 
week.8  This limits the patient profile in these facilities to individuals who 
need and can tolerate a physically demanding therapy regimen following 
hospitalization.  Commonly treated conditions in rehab hospitals include 
strokes, neurological disorders, and major lower extremity joint 
replacements (e.g., knee and hip replacements).   Hospital-based 
rehabilitation units provide similar care and are reimbursed through the 
same prospective payment system but are managed as one part of a larger 
acute-care hospital.  
In fiscal year (FY) 2012, 234 rehab hospitals provided care to Medicare 
beneficiaries accounting for a total of $2.4 billion in Medicare spending.  
Table 1 compares rehab hospitals to other types of providers of post-acute 
rehabilitation services. The comparison is based on several metrics, 
including the average amount reimbursed by Medicare per admission and 
the average length of stay.   
            Table 1: Medicare Services in Post-Acute-Care Providers (FY 2012) 
Total  Total  Average  Average 
Number of  Number of  Length of  Reimbursement 
  Facilities  Admissions  Stay   Per Admission 
Rehab hospitals  234  139,526  13.0 days  $17,164 
Hospital-based rehab units  896  192,454  12.6 days  $17,317 
Long-term acute-care hospitals  420  140,463  26.2 days  $39,493  
Home health agencies**  12,311  6.7 million  18.6 days  $5,247  
SNFs  14,938  2.4 million  41.5 days*  $12,329* 
*These figures are the average of the top and bottom quartiles presented by Medicare Payment Advisorty 
Commission. 
**Figures for home health agencies are expressed by episode of care instead of by admission.   
Sources:  Metrics for rehab hospitals and hospital rehab units are based on OIG analysis of Medicare claims data 
and metrics for other provider types are based on MedPAC, Report to the Congress:  Medicare Payment Policy, 
 
March 2014.
____________________________________________________________ 
6 OIG, Adverse Events in Skilled Nursing Facilities:  National Incidence Among Medicare 
Beneficiaries, OEI-06-11-00370, February 2014.   
7 A rehab hospital is eligible for Medicare payment through the Inpatient Rehabilitation 
Facility Prospective Payment System if it meets the criteria specified in 412.29, which 
includes a provision that at least 60 percent of a facilitys total inpatient population have one 
or more of 13 listed conditions. 
8
 42 CFR  412.622. 
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  2 
   
   
Federal Efforts to Improve Quality and Safety in Rehab 
Hospitals 
Accreditation and Routine Surveys.  As it does for all other Medicare- and 
Medicaid-certified hospitals, the Centers for Medicare & Medicaid 
Services (CMS) oversees rehab hospitals compliance with a set of 
minimum quality and safety standards known as the Conditions of 
Participation (CoPs).9  Rehab hospitals may demonstrate compliance 
through accreditation by a Medicare-approved program or through 
periodic onsite surveys by a State survey agency.10  CMS provides 
guidance to these State agencies for conducting hospital surveys in its 
State Operations Manual (SOM), including guidance specific to the rehab 
setting.11   
Quality Assessment and Performance Improvement (QAPI).  While many 
of the CoPs have an impact on quality, the QAPI CoP is the condition 
most explicitly focused on ensuring that facilities take actions to improve 
quality and safety.12  It requires rehab hospitals to track medical errors 
and adverse patient events, analyze their causes, and implement preventive 
actions and mechanisms that include feedback and learning throughout the 
hospital.  To accomplish this, rehab hospitals must measure, analyze, 
and track quality indicators, including adverse patient events, and other 
aspects of performance that assess processes of care, hospital service and 
operations.   
Reporting of Quality Data.  Congress established a quality reporting 
program for rehab hospitals and other post-acute-care providers in the 
2010 Patient Protection and Affordable Care Act (ACA).13  CMS refers to 
this program as the Inpatient Rehabilitation Facilities (IRF) Quality 
Reporting Program (QRP).14, 15  As part of the IRF QRP, CMS plans to 
adjust rehab hospital payment based on five quality measures, such as the 
percentage of residents with pressure ulcers that are new or worsened.16  
 
____________________________________________________________ 
9
 The Secretarys authority to establish the CoPs is at SSA,  1861(e)(9).  The current CoPs 
are defined at 42 CFR  482.   
10
 Social Security Act,  1864 and 1865, 42 U.S.C.  1395aa and 1395bb.
11
 CMS, SOM, Appendix A - Survey Protocol, Regulations and Interpretive Guidelines for 
Hospitals, Pub. 100-07.   
12
 42 CFR  482.21. 
13 ACA, P.L. 111-148  3004(a); SSA  1886(j)(7). 
14 76 Fed. Reg. 47836, 4787383 (Aug. 5, 2011).   
15 CMS, IRF Quality Reporting, October 24, 2014 update.  Accessed at 
http://www.cms.gov/Medicare/Quality-Initiatives-Patient-Assessment-Instruments/IRF-
Quality-Reporting/ on October 29, 2014. 
16
 79 Fed. Reg. 45871, 45918 (Aug. 6, 2014). 
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  3 
   
   
In addition to the reporting required by the IRF QRP, the Improving 
Medicare Post-Acute Care Transformation Act of 2014 (IMPACT Act) 
included new reporting requirements for post-acute-care providers, 
including rehab hospitals.17  Upon implementation, the IMPACT Act will 
require that rehab hospitals, along with other post-acute-care providers, 
report data on falls resulting in injury, pressure ulcers, and other quality 
issues.  
METHODOLOGY 
We estimated the incidence of adverse events (including temporary harm 
events) using a sample of Medicare patients who received inpatient care in  
rehab hospitals.  Our study population was composed of Medicare 
beneficiaries discharged from rehab hospitals in March 2012.  The 
beneficiaries were included only if a claim was submitted to Medicare and 
the stay began within 3 days of the beneficiarys discharge from an acute-
care hospital.   
We excluded beneficiaries who received care in hospital-based rehab units 
or through other post-acute-care providers.  The hospital-based rehab units 
associated with the excluded beneficiaries in our sample constitute 80 
percent of IRFs.18  We chose to focus instead on the smaller number of 
independently run rehab hospitals in an effort to align our findings and 
recommendations with the unique situation of these providers, which may 
not have the same capacity to provide acute-level services and receive 
separate oversight by CMS.   
Sample Selection and Profile 
Using Medicare claims data from the National Claims History (NCH) file, 
we selected a simple random sample of 417 Medicare beneficiaries out of 
the 12,328 beneficiaries who had rehab hospital stays that met the sample 
criteria defined above.  Nine sample beneficiaries had two stays during 
March.  In these cases, we reviewed both stays.  As a result, the 417 
sample beneficiaries had 426 rehab hospital stays that ended in 
March 2012.  The length of stay averaged 12.7 days. 
Data Collection 
We requested and received complete medical records for the sampled 
beneficiaries rehab hospital stays.  As part of this request, we asked 
administrators from the rehab hospitals to provide discharge summaries 
and other key medical record documents from the acute-care hospital stays 
____________________________________________________________ 
17 IMPACT Act of 2014, P.L. 113-185  2(a), SSA  1899B.  The IMPACT Act has a 
phased implementation schedule, with full implementation for rehab hospitals expected 
by October 2018.  
18
 MedPAC, Report to the Congress:  Medicare Payment Policy, March 2014, p. 243  244.   
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  4 
   
   
that preceded the rehab hospital stays.  We also requested discharge 
summaries and other key medical record documents for any acute-care 
hospital stay that occurred between the rehab hospital admission and 14 
days after discharge.  In addition to collecting the medical records, we 
collected billing data for the rehab hospital stays and any associated 
payments to hospitals from Medicare inpatient and outpatient claims files. 
Identification of Adverse and Temporary Harm Events.  We conducted a 
two-stage medical record review to identify adverse events in the sampled 
records.19  The first stage was a screening process designed to identify 
beneficiaries who may have experienced an adverse event during their 
stay(s).  During this stage, one of two registered nurses with extensive 
experience performing trigger tool reviews (referred to as screeners) 
reviewed the medical records of the sampled beneficiaries rehab and 
acute-care hospital stays, as well as associated administrative data 
collected by OIG.20  The screeners flagged the records of 182 beneficiaries 
who were likely to have experienced an adverse event.   
In the second stage, 1 or more of the 6 contracted physicians reviewed the 
medical records of the 182 beneficiaries flagged by screeners as likely to 
have experienced adverse events.  The physicians examined the charts for 
possible adverse events and described these events using a structured data 
collection instrument.        
Data Analysis 
We used the results of the review to generate estimates about adverse 
events in three categories:  incidence of events, preventability of events, 
and Medicare cost associated with events.  In addition to projected 
estimates, we described the sample when we had too few sample 
occurrences to make reliable projections.  For more information on the 
estimates and corresponding 95-percent confidence intervals, see 
Appendix C.   
Event Incidence Analysis.  To calculate incidence rates, we determined the 
percentage of sample Medicare rehab hospital patients who experienced at 
least one event (e.g., adverse event, temporary harm event) within the 
sample and projected the results to the population from which we selected 
the sample.    
Severity Analysis.  The physician reviewers assigned each event to one of 
the five harm levels, using a modified version of the National 
Coordinating Council for Medication Error Reporting and Prevention 
____________________________________________________________ 
19
 See Appendix A for a detailed description of the methodology used to identify adverse and 
temporary harm events.   
20
 See Appendix B for a description of the tool the screeners used to review the records.   
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  5 
   
   
(NCC MERP) Index.  We make a distinction between adverse events 
(levels F-I on the index) and temporary harm events (level E on the 
index) to separate events that caused the most serious harm.  Both groups 
represent harm to patients resulting from medical care or in a health care 
setting.  (See Table 3.) 
Table 3:  Modified Version of the NCC MERP Index for Categorizing Errors 
Used in the OIG Study of Adverse Events in Rehab Hospitals 
  Level   Description 
I  Harm occurred that may have contributed to or resulted in patient death 
H  Harm occurred that required intervention to sustain the patients life 
Adverse  G  Harm occurred that contributed to or resulted in permanent patient harm 
Event 
Harm occurred that prolonged the stay or led to a transfer to a different 
F  rehab hospital, another post-acute facility, or an acute-care hospital for 
observation, emergency treatment, or inpatient care 
Temporary 
E  Harm occurred that caused temporary harm that required intervention 
Harm  
Source:  Modified version of the NCC MERP Index for Categorizing Errors, Medication Errors Council Revises 
and Expands Index for Categorizing Errors:  Definitions of Medication Errors Broadened, Press Release, 
June 12, 2001. 
Preventability Analysis.  The physician reviewers also assigned each event 
to one of five preventability determinationsclearly preventable, likely 
preventable, unable to determine, likely not preventable, or clearly not 
preventable.  We calculated percentages for each preventability 
classification and projected the results to the population from which we 
selected the sample.   
Medicare Cost Analysis.  We conservatively estimated the amount 
Medicare paid for acute-care hospital stays and emergency department 
visits resulting from adverse events in rehab hospitals.  We identified the 
Medicare cost of acute-care hospital stays and/or emergency department 
visits that occurred as a result of physician-identified adverse events.  We 
projected this dollar amount to the population but present the lower bound 
of the 95-percent confidence interval associated with the cost estimate.  
We provide the conservative lower boundinstead of the point 
estimatebecause the small number of sample occurrences made the 
point estimate unreliable.  The actual amount paid by Medicare for 
adverse events in rehab hospitals is likely to be at least the value of the 
reported amount (the lower bound of the corresponding 95-percent 
confidence interval).  Further, additional costs paid by Medicare or the 
beneficiary for followup care are not included. 
Limitations 
The methodology presents several limitations.  First, all findings related to 
identified events are limited to the population from which we selected the 
sample.  Specifically, findings reflect only rehab hospital stays that ended 
in March 2012 and began within one day of the beneficiarys discharge 
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  6 
   
   
from a hospital.  Beneficiaries who received care in hospital-based rehab 
units are excluded.21  Second, it is unlikely that the study identified all 
adverse events within the sample of rehab hospital patients.  To the extent 
that we did not identify all adverse events, omissions may be the result of 
incomplete documentation in the medical records or a failure of the 
reviewers to correctly identify the patient harm.  Third, the cost estimate 
does not include all costs of care associated with adverse events, including 
additional care after the hospitalizations (such as physician office visits), 
or increased payments to the rehab hospitals.   
Standards 
This study was conducted in accordance with the Quality Standards for 
Inspection and Evaluation issued by the Council of the Inspectors General 
on Integrity and Efficiency. 
   
____________________________________________________________ 
21
 Some rehab hospitals are co-located with an acute-care provider but are managed 
independently.  These rehab hospitals were included in our sampling frame. 
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  7 
   
   
FINDINGS 
An estimated 29 percent of Medicare patients in rehab 
hospitals experienced adverse or temporary harm 
events 
Approximately 3 in 10 Medicare beneficiaries who had rehab hospital 
stays that ended in March 2012 experienced at least one adverse or 
temporary harm event during their stays (29 percent).22  The events fall 
into two groups depending on the level of harm to the patient:  adverse 
events and temporary harm events (see Table 4).   
Table 4:  Number of Adverse and Temporary Harm Events within the 
Sample by Level of Harm 
Number within 
Event Type  Level of Harm on the Modified NCC MERP Harm Index 
Sample (n=158) 
I-level:  Contributed to or resulted in patient death  3 
 
H-level:  Required intervention to sustain the patients life 7 
Adverse 
G-level:  Contributed to or resulted in permanent patient harm  3 
Events 
F-level:  Resulted in prolonged rehab hospital stay or transfer 
to an acute-care hospital for observation, emergency  33      
treatment, or inpatient care. 
Temporary  E-level:  Harm occurred that caused temporary harm that 
112 
Harm Events  required intervention 
 
Source:  OIG analysis of rehab hospital stays for 417 Medicare beneficiaries discharged in March 2012.
Ten percent of Medicare patients in rehab hospitals 
experienced adverse events 
Ten percent of Medicare patients experienced adverse events during their 
stays in rehab hospitals.  Adverse events caused harm that led to a 
prolonged rehab hospital stay or transfer to an acute-care hospital; caused 
permanent harm; required a life-sustaining intervention; or contributed to 
or resulted in death (i.e., equivalent to categories FI on the modified 
NCC MERP Index).  We estimate that 1,271 post-acute Medicare rehab 
hospital patients in our study population experienced at least one adverse 
event during their stays. 
An additional 18 percent of Medicare patients in rehab 
hospitals experienced temporary harm events 
Another 18 percent of Medicare patients experienced a temporary harm 
event during their stays in rehab hospitals.  Temporary harm events 
required medical intervention but did not prolong the stays, necessitate 
____________________________________________________________ 
22
 The combined adverse event and temporary harm event rate (29 percent) exceeds the sum 
of the adverse event rate (10 percent) and temporary harm event rate (18 percent) because of 
rounding.  For these and all other estimates presented in this report, see Appendix D for point 
estimates and confidence intervals.   
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  8 
   
   
transfer to an acute-care hospital, or life-saving intervention, nor did it 
cause permanent harm or contribute to death (i.e., equivalent to E-level 
harm on our modified NCC MERP Index).  We estimate that 2,247 post-
acute Medicare rehab hospital patients who did not experience an adverse 
event experienced at least 1 temporary harm event during their stays.  
Because these patients did not experience events causing harm equivalent 
to F  I on the harm index, they are not included in the adverse event rate.   
Less than 1 percent of Medicare patients in rehab hospitals 
experienced events that contributed to their deaths  
We estimate that 3 of 411 rehab hospital patients (0.7 percent) experienced 
adverse events that contributed to or resulted in their death.  Two 
additional patients in our sample died during their stays, but those deaths 
were not associated with an adverse event.  One adverse event that 
contributed to death involved a patient with cancer recovering in the rehab 
hospital from a recent cerebral hemorrhage.  That patient experienced a 
central line-infection characterized by sepsis-like symptoms (i.e., 
hypotension and lethargy) that resulted in death.  The physician review 
team determined that this event was likely preventable.  In a second case, 
a patient recovering from a lymphoma-related shortness of breath and 
night sweats contracted pneumonia.  The pneumonia was not initially 
recognized by staff and therefore the necessary treatment was delayed.    
Without timely treatment, the pneumonia led to sepsis along with severe 
hypotension that contributed to the patients death.  The reviewers 
determined this event to be clearly preventable.  The third event, 
determined to be clearly not preventable, involved an elderly patient who 
experienced partial paralysis and difficulty swallowing after a major 
stroke.  A feeding tube was placed, but the patient experienced chronic 
aspirations.  The aspirations led to pneumonitis and the family decided to 
withhold treatment and place the patient in hospice care. 
Less than 2 percent of Medicare patients in rehab hospitals 
experienced at least one cascade event, wherein multiple, 
related events occurred in succession 
We estimate that 1.7 percent of rehab hospital patients experienced a 
cascade event.  A cascade event is defined as a series of multiple, related 
adverse or temporary harm events that are considered a single event for 
the purpose of analysis.  In one cascade event, a patient recovering from a 
knee arthroplasty (replacement) became severely dehydrated as a result of 
a newly acquired Clostridium difficile infection.  The dehydration led to 
multiple, related events, including acute kidney injury, hyponatremia (a 
low sodium concentration in the blood), significant delirium, and 
metabolic acidosis (a pH imbalance caused by accumulation of acid).   
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  9 
   
   
Medication and patient care led to most harm affecting 
patients; infections were the least frequent cause of harm 
Consistent with findings in previous OIG studies of adverse events, 
medication and patient care led to most of the adverse and temporary harm 
events affecting patients.  The most frequent events within the sample 
were medication-induced delirium and pressure ulcers.  Table 5 presents 
the percentage of events within each of three clinical categories and lists 
subcategories of events found within the sample. 
     Table 5:  Adverse and Temporary Harm Events by Clinical Category 
Number of Sample 
Adverse and Temporary Harm Events by Clinical Category 
Events within Category  
Events Related to Medication*  46% (72) 
Delirium or change in mental status due to medications  24 
Hypoglycemic events related to medication  9 
Hypotension secondary to medication  7 
Constipation, obstipation, or ileus from medication  6 
Allergic reaction to medication  5 
Diarrhea secondary to medication  4 
Excessive bleeding due to medication  4 
Dehydration and related electrolyte disorders associated with medication  3 
Nausea and vomiting secondary to medications  3 
Thrush  3 
Other  4 
Events Related to Patient Care*  40% (63) 
Pressure ulcer  14 
Constipation, obstipation, or ileus   9 
Skin tear, abrasion, or breakdown (other than pressure ulcer)  9 
Exacerbations of preexisting conditions, including those resulting  from omissions of 
8 
care 
Fall associated with patient care  6 
Device trauma or malfunction  4 
Dehydration and related electrolyte disorders associated with patient care  3 
Venous thromboembolism, deep vein thrombosis (DVT), or pulmonary embolism (PE)   3 
Allergic reaction to equipment (e.g., tape)  2 
Edema or volume overload  2 
Other  3 
Events Related to Infections*  15% (23) 
Catheter-associated urinary tract infection (CAUTI)  5 
Soft tissue or other nonsurgical infection  4 
Clostridium difficile infection  3 
Surgical site infection (SSI)  3 
Sepsis  2 
Aspiration pneumonia and other respiratory infections  2 
Other  4 
*The sum of the percentages in this table exceed 100 percent because of rounding.  See Appendix C for point estimates and 95-
percent confidence intervals.  
Source:  OIG analysis of rehab hospital stays for 417 Medicare beneficiaries discharged in March 2012. 
 
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Forty-six percent of adverse and temporary harm 
events were preventable 
Physicians determined that 46 percent of the adverse and temporary harm 
events combined were preventable, and 51 percent were not preventable.  
Physicians were unable to make determinations for the remaining events 
because of incomplete documentation or complexities in the patients 
conditions.  Table 6 presents the percentage of events in each category of 
preventability.    
Table 6:  Adverse and Temporary Harm Events by Preventability 
Determination  
Percentage 
Preventability Assessment 
of Events  
PreventableHarm could have been avoided through improved assessment 
46% 
or alternative actions  
Clearly preventable  8% 
Likely preventable   38% 
Not preventableHarm could not have been avoided given the complexity of 
51% 
the patients condition or care required  
Clearly not preventable  6% 
Likely not preventable   46% 
Unable To Determine Preventability  3% 
As a result of rounding, subgroups for the not preventable category do not total 51 percent.   
See Appendix C for point estimates and 95-percent confidence intervals. 
Source:  OIG analysis of rehab hospital stays for 417 Medicare beneficiaries discharged in March 2012. 
When deciding whether an event was preventable, the reviewers consulted 
a list of contributing factors and selected the factors that best defined their 
rationale for the preventability determination.  Table 7 (on the next page) 
provides the preventability rationales cited by the reviewers for all events 
in the sample.   
Among the preventable events for sampled rehab hospital patients, the 
reviewers frequently cited as factors the provision of appropriate treatment 
in a substandard way and failure to adequately monitor a patients 
progress.  In one case of a preventable event, an elderly patient admitted to 
an rehab hospital after a stroke (a cerebrovascular accident, or CVA) and a 
recent diagnosis of hypertension experienced medication- related transient 
neurological symptoms (e.g., weakness and unsteady gait).  The physician 
reviewer attributed these symptoms to an unnecessarily aggressive and 
poorly monitored use of an antihypertensive medication (amlodipine).  
The rehab hospital significantly increased the dose within 24 hours of 
starting the medication.  The patients symptoms resolved after the rehab 
hospital staff reduced the dose of the antihypertensive.   
 
 
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  11 
   
   
Table 7:  Preventability Rationales for Adverse and Temporary Harm Events 
within Sample 
Number of Times 
Preventability Rationale (n=158) 
Cited By Reviewers  
Preventable Events 
Appropriate treatment was provided in a substandard way  28 
Error was related to medical judgment, skill, or patient management  23 
The patients progress was not adequately monitored  18 
Necessary treatment was not provided  17 
Patient care plan was inadequate   17 
Not Preventable Events 
Patient was highly susceptible to event because of health status  48 
Event occurred despite proper assessment and procedures followed  29 
Patients diagnosis was unusual or complex, making care difficult  12 
Care provider could not have anticipated event given information available  9 
The counts in this table exceed the total number of events because the reviewers often gave multiple rationales. 
 
Source:  OIG analysis of rehab hospital stays for 417 Medicare beneficiaries discharged in March 2012.
Not preventable events often occurred with patients who were highly 
susceptible to a particular type of event or experienced the events despite 
staff efforts to avoid harm.  In many of these cases, the reviewers noted 
that the clinicians in the rehab hospitals took reasonable precautions to 
prevent the event.  In one case, a patient recovering from a stroke (a left 
side subcortical infarction with right-sided weakness) experienced 
permanent (G-level) harm after refusing to take prescribed medications 
(i.e., clopidogrel and enoxaparin sodium) that might have prevented a 
recurrent stroke.  Without appropriate medications, the patient experienced 
an extension of the prior stroke, resulting in increasedand permanent
right-sided weakness.  The reviewers determined that in light of the 
patients decision, the event was not preventable by the staff.   
Nearly one-quarter of the Medicare patients who 
experienced an adverse or temporary harm event in a 
rehab hospital were transferred to an acute-care 
hospital for treatment 
We estimated that 3,518 Medicare rehab hospital patients experienced at 
least 1 adverse or temporary harm event.  Of these patients, an estimated  
828 (23.5 percent) went to an acute-care hospital for treatment as a result 
of the events.  This includes both those admitted as inpatients and those 
who had outpatient emergency department visits only.23  These patients 
____________________________________________________________ 
23
 Within the sample, there were 28 patients who had hospital admissions or emergency 
department visits.  Twenty-five of these patients were admitted (some of the admissions 
followed an emergency department visit), and three were treated in the emergency department 
only. 
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  12 
   
   
constitute 7 percent of all Medicare beneficiaries who had rehab hospital 
stays that ended in March 2012.   
We estimate that acute-care hospital admissions and emergency 
department visits resulting from adverse and temporary harm events for 
Medicare beneficiaries with rehab hospital stays ending in March 2012 
cost Medicare at least $7.7 million.24  Assuming that Medicare spending 
on hospitalizations due to adverse and temporary harm events in rehab 
hospitals remained constant throughout the year, Medicare inpatient 
expenditures would amount to at least $92 million annually.25  These 
estimates do not include related costs paid by Medicare or other payers
including beneficiariesfor followup medical care needed as a result of 
an event.       
   
____________________________________________________________ 
24
 As noted in the methodology section of this report, we present the estimate of cost as the 
lower bound of the confidence interval.  See Appendix C for the point estimate and 95-percent 
confidence intervals. 
25
 The annual cost estimate of $92 million assumes that Medicare expenditures for adverse 
and temporary harm events in rehab hospitals remained constant at $7.7 million in each month 
of the year.  
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  13 
   
   
CONCLUSION AND RECOMMENDATIONS 
The findings in this report confirm the need and opportunity to 
significantly reduce the incidence of adverse events in rehab hospitals, 
thereby improving the quality of care that patients receive.  Using the 
information presented in this report, health care providers and other 
stakeholders should take actions to further understand the causes of 
adverse events in rehab hospitals and reduce the incidence and impact of 
these events.  We found that 29 percent of Medicare beneficiaries 
experienced adverse events or temporary harm events during their rehab 
hospital stays, resulting in temporary harm; prolonged stays or acute-care 
hospitalizations; permanent harm; life-sustaining intervention; or death.  
This harm rate is similar to those in our previous findings for hospitals 
(27 percent) and SNFs  (33 percent).  Forty-six percent of events in rehab 
hospitals were preventable, which is again similar to our previous results 
for hospitals (44 percent) and SNFs (59 percent).  Hospitalizations 
necessitated by the events increased costs to Medicare by at least 
$7.7 million in a single month, or $92 million, annualized, in 2012, 
suggesting the opportunity for savings from reducing the incidence of 
adverse events that occur in rehab hospitals.   
The similarity of results across multiple health care settings suggests that 
research and interventions to reduce adverse and temporary harm events 
may be applicable across settings.  In our prior reports on adverse events, 
we made a series of recommendations to AHRQ, the coordinating body 
for health care quality improvement, and to CMS, the  largest health care 
payer and Federal overseer.  In response, AHRQ and CMS expressed a 
commitment to implement our recommendations and pursue strategies to 
improve care.  In this report, we recommend that AHRQ and CMS 
implement similar strategies for improved patient safety in rehab hospitals.   
AHRQ and CMS should raise awareness of adverse events in 
rehab hospitals and work to reduce harm to patients 
In response to OIG recommendations in our earlier reports on adverse 
events in hospitals and SNFs, AHRQ and CMS began collaborating to 
create a list of potentially reportable adverse events to educate health care 
staff and to measure facility performance.  CMS also began developing 
surveyor training to assist State survey agencies in assessing safety 
practices in SNFs; and, AHRQ and CMS worked to reconcile conflicts 
between the Patient Safety and Quality Improvement Act of 2005 and 
CMSs QAPI requirements.  Broadening these and other patient safety 
improvement efforts to include rehab hospitals would ensure that safe care 
practices promoted in acute-care hospitals and SNFs would extend to other 
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  14 
   
   
post-acute-care providers.  Agency response to this recommendation 
should address the following two subrecommendations:     
  AHRQ and CMS should collaborate to create and promote a list of 
potential rehab hospital events  Staff identification of patient harm 
is critical to the success of patient safety efforts in rehab hospitals, 
giving staff the opportunity to correct problems and reduce harm, as 
well as report problems contributing to events.  AHRQ and CMS 
should ensure that rehab hospital staff are able to identify a broad 
range of adverse and temporary harm events.  Toward that end, AHRQ 
and CMS should collaborate to create and disseminate a list of 
potentially reportable events for rehab hospitals.  The list should go 
beyond conventional post-acute-care issues (e.g., falls, pressure ulcers) 
and include a comprehensive range of possible patient harm, 
emphasizing the unique case mix in rehab hospitals and the 
rehabilitation needs of affected patients.  Appendix E of this report 
provides descriptions of events such a list could include.  The list may 
be extended to be consistent with the full body of research on this 
topic and should incorporate the unique challenges of this setting 
rather than duplicating lists of SNF or hospital events.     
 
  CMS should include information about potential events and 
patient harm in its quality guidance to rehab hospitals  To 
participate in the Medicare program, rehab hospitals must comply with 
the CoPs for hospitals, including requirements for a QAPI program to 
improve facility performance.  CMS reported to OIG in 2013 that it is 
testing draft interpretive guidelines for surveyors related to QAPI, 
including guidance for surveyors assessing facility efforts to improve 
patient safety.  CMS should expand this effort to include information 
on potential events in rehab hospitals and continue to seek 
opportunities to provide patient safety guidance relevant to rehab 
hospitals.  Guidance should include a definition of adverse events; a 
list of potential adverse events for staff education on the range of harm 
that patients can experience; strategies for detecting, measuring, and 
preventing adverse events; and, best practices for improving staff 
recognition and reporting of adverse events.  Issuing similar guidance 
to rehab hospitals, acute-care hospitals, and SNFs may improve 
communication and collaboration regarding shared safety concerns 
and patient transitions among facilities.   
 
 
 
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  15 
   
   
AGENCY COMMENTS AND OFFICE OF INSPECTOR GENERAL 
RESPONSE 
CMS and AHRQ concurred with our recommendations.  CMS responded that it will 
continue to collaborate with AHRQ and other partners to identify and address 
adverse events in rehab hospitals, including development of a list of potential rehab 
hospital events and expansion of the current QAPI guidance to include information 
specific to rehab hospitals.  CMS also plans to look into using the Quality 
Improvement Organization Program to assist with quality improvement efforts in 
rehab hospitals.  AHRQ responded that it will work with CMS to identify adverse 
events in rehab hospitals, as it has done for other healthcare settings.  AHRQ also 
believes it would be helpful to review the types of events identified in this report to 
determine how they relate to the current AHRQ Common Formats.  If AHRQ 
identifies a need, it will consider adding new event options in future updates to the 
Common Formats.  We look forward to receiving updates from CMS and AHRQ 
regarding their progress in implementing these recommendations.  Appendix F 
contains the full text of comments from both agencies. 
 
 
 
   
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  16 
   
   
APPENDIX A 
Methodology for Identifying Events and Determining 
Preventability 
We conducted a two-stage medical record review to identify adverse and 
temporary harm events (for the purposes of this section, we refer to adverse 
events and temporary harm events as events).  In the first stage, two 
registered nurses (referred to as screeners) identified sample beneficiaries 
who were likely to have experienced events during their rehab hospital stays. 
In the second stage, physicians reviewed the records for the subset of 
beneficiaries flagged by screeners as likely to have experienced events.  
Each record was reviewed by a screener and, if flagged, reviewed by a 
physician.      
Screening for Beneficiaries Who Likely Experienced Events.  To identify 
beneficiaries who were likely to have experienced events during their stays, 
screeners reviewed complete medical records for the rehab hospital stays and 
other information in their records.  The other information included discharge 
summaries, lab results, and other key documents from the medical records of 
the acute-care hospital stays that preceded the sampled stays.  We also 
requested discharge summaries; history and physical examinations; and 
emergency department or observation unit medical records from any hospital 
stays or emergency department visits that followed the selected admission 
and occurred up to 14 days after discharge from the rehab hospital.  In 
addition, we reviewed the claims data for the preceding and subsequent 
hospital stays and emergency department visits.   
To standardize their reviews, we required screeners use a trigger tool to 
identify triggers in the medical record.  The trigger tool was based on the IHI 
Global Trigger Tool (GTT) instrument and was modified for the post-acute 
rehab hospital environment.  If screeners found a trigger, they explored the 
record further to determine whether events occurred and, if so, documented 
the level of harm.  Of the 417 beneficiaries in the sample, screeners 
flagged 182 beneficiaries records (44 percent) for physician review.   
The screening process enabled us to reduce the number of cases requiring 
second-level review of the full medical records by a physician.  As in the 
other OIG studies of adverse event incidence, physician reviewers indicated 
that the results of the screening methods helped them to readily identify 
potential events for consideration. 
Physician Identification of Events within Flagged Rehab Hospital Records.  
One of 6 contracted physicians reviewed the medical records for each of the 
182 beneficiaries flagged in the initial screening.  The physician reviewers 
represented a variety of specializations and experience: a 
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  17 
   
   
neurologist/physiatrist with experience as a medical director of a rehab 
hospital, an infectious disease specialist, a cardiologist, an orthopedic 
surgeon, an internal medicine specialist, and a geriatrician with extensive 
experience as a SNF medical director.  All six had many years of clinical 
experience, and five had prior experience in detecting adverse events in 
retrospective medical record reviews.  Four of the six served as physician 
reviewers for the 2010 OIG study of adverse events in hospitals, and five of 
the six served as physician reviewers for the 2014 OIG study of adverse 
events in SNFs. 
To identify events experienced by patients during their stays, the 
physicians reviewed results of the screeners reviews as well as all the 
information made available to the screeners.  In addition to reviewing  
records from the rehab hospitals, the physicians reviewed documents and 
data from any preceding and subsequent hospital stays to look for 
evidence of events that occurred during the rehab hospital stays.   
Over 10 weeks, physician reviewers examined the 191 records of the 
182 beneficiaries flagged by screeners.  Physician reviewers used a 
structured medical review protocol that required them to describe each harm 
event and specify the level of harm experienced by the patient.  Harm was 
categorized in accordance with a modified version of the NCC MERP Index 
of Categorizing Medication Errors (see Table 3). 
We recorded all events that physician reviewers determined to be attributable 
to care provided during the rehab hospital stays.  We excluded events that 
were part of the underlying disease process, occurred before the beneficiary 
entered the rehab hospital, or were attributable to the care provided in a 
preceding hospitalization.  When an initial event caused a series of related 
and dependent events, we combined the events into a cascade event and 
counted it as a single event.  When a patient experienced a specific type of 
event more than once during a stay (e.g., two episodes of hypoglycemia), we 
counted them as a single event if the second event occurred within 7 days of 
the first and occurred under the same circumstances.  We counted them as 
separate events if the second event occurred more than 7 days after the first 
or if the circumstances that led to the event were substantially different.    
   
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  18 
   
   
Determining Preventability for Each Event.  Physician reviewers included an 
assessment of the extent to which events were preventable and factors that 
contributed to events.  They used a five-point response scale, described in 
Table A-1.  Assessing an event as clearly preventable or clearly not 
preventable required a greater degree of certainty on the part of the reviewer.  
Although the five-point scale enabled physicians to make more precise 
determinations, we collapsed the clearly and likely subcategories in our 
primary statistics.   
Table A-1:  Preventability Scale for Categorizing Adverse Events  
Likelihood That Event Could Have Been Prevented: 
Clearly PreventablePatient harm could definitely have been avoided through 
improved assessment or alternative actions. 
Preventable 
Events 
Likely PreventablePatient harm could have been avoided through improved 
assessment or alternative actions. 
Likely Not PreventablePatient harm could not have been avoided given the 
Not  complexity of the residents condition or the care required.  
Preventable 
Events  Clearly Not PreventablePatient harm could definitely not have been avoided 
given the complexity of the residents condition or the care required.  
Unable to 
Unable to DeterminePhysicians were unable to determine preventability 
Determine 
because of incomplete documentation or case complexity.  
Events 
Physician reviewers used a decision algorithm to improve consistency in 
making preventability determinations.  We worked with the reviewers to 
develop the algorithm during practice reviews consisting of a series of 
questions that led the reviewers to a suggested response.  Questions 
addressed issues such as whether there was a medical error, whether the 
event could have been anticipated, and how frequently the event occurs 
given proper care.  Physicians did not automatically accept the suggested 
response, but determined whether it was appropriate in the particular case.   
To make distinctions about the circumstances in each case, physicians used 
their clinical experience and judgment.  They considered all evidence in the 
medical records, including staff actions and the residents conditions.  
Physicians also used information about accepted standards of care, the 
frequency with which certain events occurred despite appropriate assessment 
and care, the physicians individual clinical experiences, guidance developed 
during the review process, and group discussion of cases.  Using a list of 
contributing factors gleaned from prior research and experience in prior OIG 
studies of adverse event incidence, physicians indicated the rationale for 
each determination and provided a narrative description for each case. 
Consistency Discussions and Review.  Throughout our medical records 
review, we facilitated nine conference calls during which physician 
reviewers discussed the review protocol and sample cases that either were 
complex or had possible implications for other cases.  The goal of these calls 
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  19 
   
   
was to reach consensus on difficult and complex cases and to establish 
consistency among reviewers.  On the calls, physicians solicited the opinions 
of the other panelists to help make determinations on difficult cases.  During 
the weekly conference calls, we required physicians to discuss all clearly 
preventable and clearly not preventable determinations and events that 
potentially contributed to a patients death, and we encouraged them to bring 
other cases for discussion if they had difficulty or felt the cases would 
inform other determinations.  Physicians also often brought cases to group 
discussion if they involved care specific to another physicians 
specialization.  We documented the discussions and conclusions made during 
these weekly calls, continually revising a written physician guidance 
document to further promote consistency.  Physicians reviewed or discussed 
the majority of the identified events as well as possible events, which the 
group ultimately determined did not meet the study threshold.         
Following the medical records review, we analyzed the identified events, 
harm-level determinations, and preventability determinations to identify any 
inconsistencies and discussed these with physician reviewers.  This process 
resulted in changes to the initial determinations of some events.   
 
 
 
 
 
 
   
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  20 
   
   
APPENDIX B 
Triggers Listed on the Trigger Tool Worksheet 
Table B-1:  Trigger Tool Worksheet 
  Care Module Triggers    Care Module Triggers (continued) 
C1  Acute mental status change  C26  Diagnostic radiology or imaging studies 
C2  Aspiration  C27  Care-Other 
C3  Call to physician or family members    Medication Module Triggers 
Code, Rapid Response Team (RRT), or Emergency 
C4  M1  Abnormal electrolytes 
Medical Services (EMS) 
C5  Death  M2  Abrupt medication stop 
C6  Drop in hemoglobin/hematocrit  M3  Anti-emetic use 
C7  Studies for emboli, PE or DVT  M4  Diphenhydramine (Benadryl) use  
C8  Fall  M5  Elevated international normalized ration (INR) 
C9  Family complaint  M6  Glucose <50, Glucagon or Dextrose supplement  
C10  Any infection  M7  Abrupt onset hypotension 
C11  New or increased diuretics  M8  Naloxone (Narcan) use 
C12  High or low body temperature  M9  Sodium Polystyrene (Kayexalate administration) 
C13  Stroke or transient ischemic attack in rehab hospital  M10  Abnormal drug levels 
C14  New onset of incontinence  M11  Thrombocytopenia 
C15  Insertion or use of urinary catheter  M12  Total WBC < 3,000 or >12,000 
Functional Independence Measure  [FIM score] 
C16  M13  Vitamin K administration (Aqua-Mephyton) 
decrease or no change from admission to discharge 
C17  Resident incident or accident  M14  Antibiotics started in the rehab hospital 
C18  Pressure ulcer  M15  Increasing pain medication needs 
C19  Emergency department visit  M16  Administration of parenteral fluid 
Transfer to acute-care hospital, observation unit, or 
C20  M17  Medication-Other 
unplanned transfer to another rehab hospital 
C21  Restraint use    Procedure Module Triggers 
C22  Rising serum creatinine  P1  Postoperative/post-procedure complication 
Procedure reintubation/new Biphasic Positive Airway 
C23  Urinary retention  P2  Pressure (BiPAP) / new Continuous Positive Airway 
Pressure (CPAP) 
C24  New onset diarrhea   P3  Procedure-Other 
C25  Prolonged constipation      
Source:  OIG, Adverse Events in Inpatient Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110). 
 
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  21 
   
   
APPENDIX C 
Estimates, Confidence Intervals, and Key Statistics 
Table C-1:  Beneficiary Level Estimates, Confidence Intervals, and Key Statistics  
95-Percent  95-Percent   
Confidence Interval  Confidence Interval 
Sample  Lower  Upper  Lower  Upper 
 
Estimate Description  Size (n)  Percentage   Bound  Bound  Frequency   Bound  Bound 
Event Experiences for All Beneficiaries   
Experienced at least one adverse event   417  10.3%  7.8%  13.6%  1271  916  1626  1 
Experienced at least one temporary 
harm event and did not experience an  417  18.2%  14.8%  22.2%  2247  1796  2698  2 
adverse event  
Experienced at least one adverse event 
417  28.5%  24.5%  33.0%  3518  2991  4046  3 
or at least one temporary harm event  
Experienced only preventable adverse 
417  15.1%  12.0%  18.8%  1863  1444  2281  4 
and temporary harm events 
Experienced only preventable adverse 
417  6.7%  4.7%  9.5%  828  535  1120  5 
events  
Experienced only preventable 
temporary harm events and no adverse  417  7.9%  5.7%  10.9%  976  660  1291  6 
events  
Experienced adverse events that 
417  0.7%  0.2%  2.2%  --  --  --  7 
contributed to death*  
Experienced transfer to an acute-care 
hospital because of an adverse or  417  6.7%  4.7%  9.5%  828  535  1120  8 
temporary harm event 
Experienced a cascade adverse event*  417  1.7%  0.8%  3.4%  207  57  357  9 
Beneficiaries Who Experienced at Least One Adverse Event or One Temporary Harm Event   
Experienced at least one transfer to an 
acute-care hospital that was the result  119  23.5%  16.8%  31.9%  828  535  1120  10 
of an adverse or temporary harm event  
* We are unable to reliably project the frequency estimates for this item because of the small number of sample occurrences.   
Source:  OIG analysis of rehab hospital stays and Medicare claims for 417 Medicare beneficiaries discharged in March 2012. 
 
Table C-2:  Estimates, Confidence Intervals, and Key Statistics
95-Percent   
Confidence Interval 
Sample  Lower  Upper   
Estimate Description  Size (n)  Percentage   Bound  Bound 
Clinical Category for All Adverse and Temporary Harm Events   
  Medication adverse and temporary harm events  158  45.6 %  37.9%  53.2%  11 
  Patient care adverse and temporary harm events  158  39.9%  31.9%  47.8%  12 
  Infection adverse and temporary harm events  158  14.6%  9.2%  19.9%  13 
Preventability Classification for All Adverse Events and Temporary Harm Events   
  Preventable adverse and temporary harm events  158  46.2%  38.0%  54.4%  14 
o Clearly preventable adverse and temporary harm events  158  8.2%  3.7%  12.8%  15 
o Likely preventable adverse and temporary harm events  158  38.0%  29.9%  46.1%  16 
  Not preventable adverse and temporary harm events  158  51.3%  42.9%  59.6%  17 
o Clearly not preventable adverse and temporary harm events  158  5.7%  2.2%  9.2%  18 
o Likely not preventable adverse and temporary harm events  158  45.6%  37.7%  53.5%  19 
  Unable to determine adverse and temporary harm events  158  2.5%  0.1%  4.9%  20 
 
Source:  OIG analysis of RH stays and Medicare claims for 417 Medicare beneficiaries discharged in March 2012. 
 
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  22 
   
   
Table C-3:  Estimates, Confidence Intervals, and Key Statistics 
95-Percent   
Confidence Interval 
Estimates of Acute-Care Hospitalizations and Medicare Payments Associated  Lower  Upper   
with Adverse Events in Rehab Hospitals  Total     Bound  Bound 
Acute-care hospitalizations associated with adverse and temporary harm events  887  564  1210  90 
Medicare payment for acute-care hospitalizations associated with adverse events in RHs  $16,325,640  $7,670,132  $24,981,147  88 
Source:  OIG analysis of rehab hospital stays and Medicare claims for 417 Medicare beneficiaries discharged in March 2012   
 
   
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  23 
   
   
APPENDIX D 
Rates of Adverse Events and Temporary Harm Events in 
Rehab Hospitals by Patient Days and by Admissions 
Health care facilities commonly measure adverse events by incidence 
density, which takes into account the period during which patients are 
observed.  For example, incidence density is often used in measuring 
healthcare-acquired infections because risk can increase with the length of 
exposure to the health care environment.26  IHI, a nonprofit advisory group 
to hospitals, cites advantages to using incidence density metrics over 
standard incidence rates that measure the number of events per patient.27  
IHI reports that measuring total events by patient days or hospital 
admissions enables hospitals to count multiple events experienced by the 
same beneficiary.   
The sample of 417 Medicare beneficiaries discharged during 
March 2012 included 426 total rehab hospital stays and a combined total 
of 5,400 patient days in the facilities.  We calculated patient days by 
subtracting the admission date for each rehab hospital stay from its 
discharge date.  Table D-1 provides ratios for adverse events and 
temporary harm events in the sample per 1,000 patient days and per 100 
admissions. 
Table D-1:  Rates of Adverse and Temporary Harm Events in the Sample by 
Patient Days and Rehab Hospital Admissions 
Per 1,000   Per 100  
Category 
Patient Days  Admissions 
Adverse events   9  11 
Temporary harm events   21  26 
Adverse and temporary harm events combined  29  37 
 
Source:  OIG analysis of rehab hospital stays for 417 Medicare beneficiaries discharged in March 2012
 
 
 
 
   
____________________________________________________________ 
26 K.M. Arias, Outbreak Investigation, Prevention, and Control in Health Care Settings, 
Second Edition, 2009, Jones and Bartlett Publishers, pp. 330331. 
27 IHI, IHI Global Trigger Tool for Measuring Adverse Events, Second Edition, 2009, p. 13. 
 
Adverse Events in Rehabilitation Hospitals:  National Incidence Among Medicare Beneficiaries (OEI-06-14-00110)  24 
   
   
APPENDIX E 
Adverse Events and Temporary Harm Events Identified in the Sample 
Tables E-1 and E-2 contain information about adverse events and temporary harm 
events identified in the sample, including description, harm level, and 
preventability.  Table E-1 contains information about adverse events 
(46 adverse events).28  Table E-2 contains information about temporary harm 
events (112 events).   
 
Table E-1:  Adverse Events by Clinical Category, Harm Level, and Preventability (n=46)  
Harm 
Adverse Event  Preventability   
Level 
 
Adverse Events Related to Medication (18) 
 
Delirium or change in mental status due to medications (5) 
1. Multiple episodes of unresponsiveness secondary to benzodiazepine (clonazepam) and     
H CP 28 
hypnotic (zolpidem) requiring an emergency reversal agent (flumazenil) 
   
2. Confusion and lethargy secondary to opioids (oxycodone and tramadol) that extended stay  F LNP 30 
3. Lethargy and syncopal episode secondary to opioid (hydrocodone/acetaminophen) resulting in     
F LP 47 
transfer to an acute-care hospital 
4. Confusion and agitation secondary to opioids (oxycodone) resulting in transfer to an acute-care     
F LNP 129 
hospital 
5. Cascade in which medication-induced confusion and agitation secondary to benzodiazepine     
F LP 133 
(lorazepam) led to patient pulling urinary catheter with resultant injury and bleeding 
Excessive bleeding due to medication (3)   
1. Bleeding from gastric ulcers secondary to anticoagulants (warfarin and aspirin) resulting in     
H CP 54 
transfer to an acute-care hospital 
2. Gastrointestinal hemorrhage secondary to anticoagulants (dabigatran and aspirin) resulting in     
F CNP 73 
transfer to an acute-care hospital 
3. Peri-incisional hematoma in thigh secondary to multiple anticoagulants (warfarin, aspirin, and     
F CP 121 
enoxaparin sodium) 
Hypotension secondary to medication (3)   
1. Hypotensive-event (syncope) secondary to beta-blocker used to treat multiple conditions, 
F  LP  86 
including hypertension (metoprolol), resulting in transfer to an acute-care hospital 
2. Hypotension secondary to medication used to treat fluid retention (hydrochlorothiazide)  F  LNP  148 
3. Orthostatic hypotension secondary to medication used to treat hypertension (hydralazine)  F  LP  161 
Dehydration and related electrolyte disorders associated with medication (2)   
1. Hyperkalemia secondary to diuretic and antihypertensive (spironolactone)  H  LP  63 
2. Acute renal failure, hyperkalemia (high potassium), and dehydration secondary to diuretics 
F  CP  130 
resulting in transfer to an acute-care hospital 
Diarrhea secondary to medication (2)   
1. Diarrhea and dehydration secondary to antibiotics and resulting in transfer to an acute-care 
F  LNP  110 
hospital 
2. Diarrhea and dehydration from antibiotic  F  LNP  1003 
Continued on next page.   
 
____________________________________________________________ 
28 Patient harm is classified according to a modified version of the NCC MERP Index for Categorizing 
Errors (EI) presented in Table 3.  Preventability determinations were selected from the following 
options:  CP for clearly preventable, LP for likely preventable, LNP for likely not preventable, CNP for 
clearly not preventable, and UTD for unable to determine. 
Adverse Events in Inpatient Rehabilitation Facilities (OEI-06-14-00110)  25 
 
   
   
Table E-1:  Adverse Events by Clinical Category, Harm Level, and Preventability (n=46) 
(Continued) 
Harm 
Adverse Event  Preventability   
Level 
 
Adverse Events Related to Medication (18) (continued) 
Nausea and vomiting secondary to medications (2)   
1. Nausea, cramping, and vomiting due to medications given to treat constipation (magnesium 
hydroxide) and gastrointestinal symptoms (metoclopramide) resulting in transfer to an acute-care  F  LNP  17 
hospital 
2. Nausea and vomiting due to opioid pain medication (hydrocodone)  F  LP  165 
Hypoglycemic events related to medication (1)   
1.  Multiple, severe symptomatic hypoglycemic episodes characterized by a period of 
H  LP  25 
unresponsiveness and blood glucose of 29 resulting in transfer to an acute-care hospital 
Adverse Events Related to Patient Care (17)   
Exacerbations of preexisting conditions and other deteriorating medical conditions (7)   
1. Omission of care led to congestive heart failure exacerbation resulting in transfer to an 
F  CP  40 
acute-care care hospital 
2. Sudden onset of acute respiratory decompensation resulting in transfer to an acute-care hospital  H  LNP  55 
3. Insufficient treatment of a preexisting left subcortical infarction due to patient refusing medication 
led to an extension of the infarction resulting in transfer to an acute-care hospital caused in part  G  LNP  56 
by patients refusal to comply with associated medication regimen 
4. Gastric ulcer found by esophagogastroduodenoscopy (EGD) while on aspirin and steroids  F  LNP  104 
5. Cascade event in which failure to monitor progressive dysphagia led to dehydration resulting in 
transfer to an acute-care hospital related to poor transition of care with failure to provide BiPAP in  F  LP  109 
patient with Obstructive Sleep Apnea 
6. Cardiac arrest requiring Advanced Cardiovascular Life Support (ACLS) and transfer to 
H  CP  179 
acute-care hospital 
7. Acute change in motor function with worsening lethargy (possible CVA) resulting in transfer to an 
F  UTD  183 
acute-care hospital 
Dehydration and related electrolyte disorders associated with patient care (2)   
1. Acute renal injury due to inadequate management of fluid intake resulting in dehydration and 
F  LP  58 
transfer to an acute-care hospital 
2. Significant dehydration due to inadequate hydration resulting in hospitalization  F  CP  182 
Pressure ulcer (2)   
1. Progression of stage II pressure ulcer on buttocks to a stage IV pressure ulcer  G  CP  172 
2. Progression of stage I pressure ulcer on heel to a stage IV ulcer  G  CP  177 
Venous thromboembolism, DVT, or PE (2)       
1. Common femoral vein DVT resulting in transfer to an acute-care hospital  F  LNP  80 
2. DVT resulting in transfer to an acute-care hospital  F  LNP  125 
Other patient-care events (4)   
   
1. Allergic reaction (pruritus) to post-surgical tape  F LNP 4 
2. Cascade in which continuous passive movement (CPM) and anticoagulation (warfarin and 
   
enoxaparin sodium) led to bleeding and worsening contracture resulting in transfer to an acute- F LP 21 
care hospital. 
3. Hemorrhagic cystitis in patient associated with Foley catheter and anticoagulant (warfarin)  F  LP  10 
4. Dehiscence of surgical wound  F  UTD  93 
Adverse Events Related to Infections or Antibiotics (11)   
Catheter-associated urinary tract infection (CAUTI) (3)   
1. Catheter-associated urinary tract infection (Escherichia coli)  F  LP  46 
2. Catheter-associated urinary tract infection (Enterobacter)  F  LP  106 
3. Catheter-associated urinary tract infection resulting in transfer to an acute-care hospital  F  LNP  107 
Continued on next page.   
 
Adverse Events in Inpatient Rehabilitation Facilities (OEI-06-14-00110)  26 
 
   
   
Table E-1:  Adverse Events by Clinical Category, Harm Level, and Preventability (n=46) 
(Continued) 
Harm 
Adverse Event  Preventability   
Level 
Adverse Events Related to Infections (11) (continued)   
Clostridium difficile infection (2)   
1.  Clostridium difficile infection secondary to antibiotics  F  LP  35 
2.  Cascade event in which a Clostridium difficile infection (while being treated with ciprofloxacin) 
led to significant dehydration, acute kidney injury, hyponatremia, confusion, and metabolic  F  LP  85 
acidosis resulting in transfer to an acute-care hospital 
Sepsis (2)   
1.  Cascade event in which delayed recognition of pneumonia led to sepsis and then severe 
I  CP  29 
hypotension resulting in transfer to an acute-care hospital and finally death 
2.  Cascade event in which a urosepsis (characterized by increasing confusion) developed into 
septic shock, which led to kidney failure and hypotension resulting in transfer to an acute-care  H  LP  160 
hospital 
Other infection adverse events (4)       
1.  Recurrent aspiration in post-stroke patient with feeding tube resulted in the patient's death  I  CNP  19 
2.  Peripherally inserted central catheter infection characterized by sepsis-like symptoms 
I  LP  84 
(hypotension, lethargy) resulting in transfer to an acute-care hospital and, finally, death 
3.  Deep pelvic infection resulting in transfer to an acute-care hospital  F  LP  187 
4.  Cascade event in which aspiration pneumonia led to hypotension resulting in transfer to an 
F  LP  117 
acute-care hospital 
Source:  OIG analysis of rehab hospital stays for 417 Medicare beneficiaries discharged in March 2012.   
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Adverse Events in Inpatient Rehabilitation Facilities (OEI-06-14-00110)  27 
 
   
   
Table E-2:  Temporary Harm Events by Clinical Category and Preventability (n=112) 
Temporary Harm Event  Preventability   
 
Temporary Harm Events Related to Medication (54) 
Medication-induced delirium or other change in mental status (19)   
1.  Confusion and disorientation from medication used to treat overactive bladder (oxybutynin)  LNP  6 
2.  Multiple episodes of oversedation due to opioids in patient complicated by patient stealing and self-
LNP  8 
administering additional medications 
3.  Significant drowsiness and unresponsiveness secondary to antipsychotic (quetiapine)  LNP  14 
4.  Significant confusion due to opioids (oxycodone/acetaminophen)  LP  15 
5.  Multiple episodes of confusion secondary to opioids (oxycodone) and hypnotic (zolpidem)  LNP  16 
6.  Multiple episodes of confusion and decreased cognitive performance secondary to opioids 
LNP  33 
(hydromorphone) 
7.  Significant lethargy secondary to antipsychotic (haloperidol)  LP  45 
8.  Lethargy and anxiety secondary to antidepressant (serotonin antagonist and reuptake inhibitor (SARI))  LP  52 
9.  Confusion and lethargy secondary to opioid pain medication (hydrocodone/acetaminophen)  LP  78 
10.  Delirium secondary to medication used to treat Parkinson's disease (carbidopa/levodopa)  LNP  135 
11.  Lethargy and confusion secondary to multiple medications, including an opioid analgesic 
(hydrocodone/acetaminophen), an atypical antipsychotic (quetiapine), and a benzodiazepine  LP  137 
(clonazepam). 
12.  Weakness and imbalance secondary to medication used to lower blood pressure (amlodipine)  LP  147 
13.  Lethargy secondary to opioid pain medications (hydromorphone and fentanyl)  LNP  153 
14.  Lethargy secondary to opioid pain medication (hydromorphone)  UTD  154 
15.  Lethargy, increased confusion and belligerence secondary to antihistamine (hydroxyzine) used to treat 
LNP  159 
worsening of chronic dermatitis 
16.  Hallucinations secondary to hypnotic (zolpidem)  LP  164 
17.  Confusion secondary to benzodiazepine (alprazolam)  LP  171 
18.  Lethargy secondary to opioid pain medication (oxycodone/acetaminophen)  LP  173 
19.  Sedation and lethargy secondary to antianxiety medications (benzodiazepines)  CP  175 
Hypoglycemic events related to medication (8)   
1.  Asymptomatic hypoglycemia with a blood glucose of 47  LNP  31 
2.  Severe episode of hypoglycemia with a blood glucose of 25  LNP  37 
3.  Multiple episodes of asymptomatic hypoglycemia with blood glucose readings of 38 and 41  LP  57 
4.  Symptomatic blood glucose characterized by cold and clammy skin and a blood glucose of 47  LP  66 
5.  Asymptomatic hypoglycemic episode with a blood glucose of 39  LNP  74 
6.  Symptomatic hypoglycemic episode characterized by cold, clammy skin and lethargy and labile blood 
LNP  90 
glucose with a blood glucose of 45 
7.  Symptomatic hypoglycemia characterized by blood glucose of 65 and nausea secondary to insulin 
management  LNP  122 
8.  Asymptomatic hypoglycemia characterized by blood glucose of 44 secondary to insulin management  LNP  167 
Constipation, obstipation, and ileus from medication (6)   
1)  Significant and prolonged constipation due to pain medications  LNP  9 
2)  Significant constipation secondary to opioid pain medication (hydrocodone/acetaminophen)  LP  139 
3)  Significant constipation associated with post-surgery opioid pain medication (oxycodone)  CNP  144 
4)  Significant constipation associated with post-surgery opioid pain medication (oxycodone)  CNP  145 
5)  Significant constipation associated with post-surgery opioid pain medication 
LNP  158 
(hydrocodone/acetaminophen) 
6)  Constipation  LNP  1002 
Continued on next page.   
 
 
 
 
Adverse Events in Inpatient Rehabilitation Facilities (OEI-06-14-00110)  28 
 
   
   
Table E-2:  Temporary Harm Events by Clinical Category and Preventability (n=112) (Continued) 
Temporary Harm Event  Preventability   
Temporary Harm Events Related to Medication (54) continued   
Allergic reactions to medications (5)   
1.  Allergic reaction to antibiotic  LNP  111 
2.  Allergic reaction to antibiotic (nitrofurantoin)  CP  120 
3.  Allergic reaction (rash) secondary to antibiotic (cephalexin)  LNP  136 
4.  Allergic reaction (multiple episodes of itching) secondary to opioid pain medication (hydromorphone)  CP  143 
5.  Allergic reaction (itching and hives) to melatonin  CNP  166 
Hypotension secondary to medication (4)     
1.  Orthostatic hypotension secondary to diuretic (furosemide)  LP  61 
2.  Symptomatic bradycardia due to beta-blocker (metoprolol)-induced hypertension  LNP  76 
3.  Orthostatic hypotension secondary to medication used to treat hypertension (hydralazine)  LNP  87 
4.  Cascade event in which dehydration and medication used to treat hypertension (Lisinopril) led to 
LP  156 
hypotension and then acute kidney injury 
Thrush (3)     
1.  Esophageal Candida infection secondary to antibiotics  LNP  50 
2.  Esophageal Candida infection secondary to immunosuppressant (prednisone) used to treat inflammatory 
LNP  114 
diseases 
3.  Oral thrush  CNP  151 
Adverse reaction to medication (nonallergic or not otherwise specified) (2)     
1.  Excessive night sweats secondary to opioid pain medication (oxycodone)  LNP  11 
2.  Irritation of larynx secondary to inhaler-delivered asthma medication (fluticasone/salmeterol)  LNP  83 
Diarrhea secondary to medication (2)     
1.  Multifactorial diarrhea secondary to antibiotics, stool softeners, and enteral feeding  CNP  42 
2.  Significant diarrhea secondary to stool softener (docusate sodium)  LP  62 
Other medication temporary harm events (5)   
1.  Hyponatremia secondary to medication used to treat hypertension and congestive heart failure by treating 
LP  150 
fluid retention (hydrochlorothiazide) 
2.  Bleeding from surgical incision site with associated decreased hemoglobin secondary to anticoagulants 
LP  72 
(clopidogrel and rivaroxaban) 
3.  Fall associated with lethargy secondary to opioid (hydrocodone/acetaminophen) and opiate (morphine 
LNP  79 
sulfate) pain medications 
4.  Nausea and vomiting due to medications (pantoprazole) given to treat gastro esophageal reflux disease    LP  67 
5.  Urinary retention secondary to antihistamine (diphenhydramine)  LP  174 
Temporary Harm Events Related to Patient Care (46)   
Pressure ulcers (12)   
1.  Multiple, stage I pressure ulcers on sacrum, coccyx and buttocks  LP  5 
2.  Stage I pressure ulcer on buttocks  LP  24 
Continued on next page.   
 
   
Adverse Events in Inpatient Rehabilitation Facilities (OEI-06-14-00110)  29 
 
   
   
Table E-2:  Temporary Harm Events by Clinical Category and Preventability (n=112) (Continued) 
Temporary Harm Event  Preventability   
Temporary Harm Events Related to Patient Care (46) (continued)    
Pressure ulcers (12) (continued)    
3.  Stage I pressure ulcer on heel  LP  43 
4.  Progression of pressure ulcer from redness to excoriation with redness  LNP  44 
5.  Unstageable pressure ulcer on rear of leg  LNP  49 
6.  Stage I/II pressure ulcer on leg due to poor-fitting prosthesis  LP  51 
7.  Progression of Stage I pressure ulcer on right heel to Stage II  LP  69 
8.  Stage II pressure ulcer on buttocks  LP  94 
9.  Stage I pressure ulcers on heels  LP  108 
10.  Stage II pressure ulcer at coccyx  LP  132 
11.  Stage I pressure ulcer on sacral coccyx  LP  141 
12.  Unstageable pressure ulcer on heel (described as without breakdown)  LNP  170 
Constipation or obstipation from patient care (9)   
1.  Constipation with x-ray evidence of small bowel ileus during stay  UTD  20 
2.  Symptomatic constipation and ileus secondary to inadequate bowel care  LP  38 
3.  Symptomatic constipation and ileus characterized by nausea, vomiting, and abdominal distention   LNP  82 
4.  Prolonged constipation secondary to inadequate bowel care  LP  95 
5.  Significant constipation with impaction   LNP  100 
6.  Symptomatic constipation with x-ray showing fecal stasis   LNP  102 
7.  Significant constipation documented by abdominal x-ray  LNP  105 
8.  Significant constipation with impaction  CNP  116 
9.  Obstipation with impaction associated with inadequate bowel care  LP  140 
Skin tear, abrasion, or breakdown (other than pressure ulcer) and other minor skin event (8)   
1.  Skin tear with fungal infection that developed under brace  LP  7 
2.  Skin abrasions on elbows and knees  LNP  59 
3.  Rash on thorax, hip, and buttocks  LNP  60 
4.  Skin tears on right elbow and buttocks  LNP  103 
5.  Skin excoriation on buttocks  LP  119 
6.  Excoriation on buttocks and scrotum attributed to medication-induced delirium and agitation  LNP  134 
7.  Skin tears on legs  LNP  138 
8.  Skin tear on leg  LNP  184 
Fall associated with patient care (6)   
1.  Fall with injury (bruising) to lower back and head  LNP  53 
2.  Fall resulting in skin tear on left leg  LNP  127 
3.  Fall with injury to nose (laceration)  LNP  131 
4.  Fall with minor injuries to hip (pain) and head (temporal area swelling)  LNP  142 
5.  Fall from bed with minor injuries (elbow, knees, and small skin tear)  LP  162 
6.  Fall from wheelchair with minor injury to head and skin tear on knee  LNP  176 
Device trauma or malfunction (4)     
1.  Clotted arteriovenous shunt (dialysis access device)  LP  34 
2.  Trauma due to multiple failed Foley catheter insertions  LP  163 
3.  Hematuria secondary to intermittent catheterization  LNP  185 
4.  Skin ulcer under head of penis due to intermittent urinary catheterization  LNP  186 
Continued on next page.   
Adverse Events in Inpatient Rehabilitation Facilities (OEI-06-14-00110)  30 
 
   
   
Table E-2:  Temporary Harm Events by Clinical Category and Preventability (n=112)  
Temporary Harm Event  Preventability   
Temporary Harm Events Related to Patient Care (46) (continued)   
Edema or volume overload (2)   
1.  Temporary edema at intravenous needle insertion site following blood infusion  LNP  1 
2.  Volume overload manifested by shortness of breath and lower extremity pitting edema  LP  23 
Other patient care temporary harm events (5)   
1.  Allergic reaction (skin irritation) to medical adhesive tape  LNP  146 
2.  Superficial burn on chest from hot beverage  CNP  32 
3.  Mild renal impairment and dehydration related to fluid management and trimethoprim and  LNP  128 
sulfamethoxazole 
4.  Muscle strain with chest wall pain due to belt used in therapy  LNP  81 
5.  Significant DVT in right lower extremity despite appropriate prophylaxis in patient with history of DVT  LNP  112 
Temporary Harm Events Related to Infections (12)   
Soft tissue or other nonsurgical infection (4)   
1.  Yeast infection related to persistent moisture in the perineal area  LP  68 
2.  Yeast infection and rash under breast  LNP  75 
3.  Blisters and erythema on right thigh  LP  126 
4.  Erythema of the scrotum  LNP  169 
Surgical site infection (SSI) (3)   
1.  Superficial infection that developed on existing wound site  LP  3 
2.  Surgical site infection at site of hip surgery  LP  71 
3.  Cellulitis on left leg  LNP  96 
Catheter-associated urinary tract infection (2)   
1.  Catheter-associated urinary tract infection (Citrobacter freundii)  LNP  13 
2.  Catheter-associated urinary tract infection  LNP  101 
Other (3)     
1.  Clostridium difficile infection secondary to antibiotics  LNP  64 
2.  Scabies (pruritic bumps on back and hand)  LNP  115 
3.  Vaginal candidiasis  LNP  1001 
Source:  OIG analysis of rehab hospital stays for 417 Medicare beneficiaries discharged in March 2012.   
 
 
 
 
Adverse Events in Inpatient Rehabilitation Facilities (OEI-06-14-00110)  31 
 
   
   
APPENDIX F 
Agency Comments:  Centers for Medicare and Medicaid Services 
 
Adverse Events in Inpatient Rehabilitation Facilities (OEI-06-14-00110)  32 
 
   
   
   
Adverse Events in Inpatient Rehabilitation Facilities (OEI-06-14-00110)  33 
 
   
   
Agency Comments: Agency for Healthcare Research and Quality 
 
 
 
 
 
Adverse Events in Inpatient Rehabilitation Facilities (OEI-06-14-00110)  34 
 
   
   
 
ACKNOWLEDGMENTS 
This report was prepared under the direction of Kevin K. Golladay, Regional 
Inspector General for Evaluation and Inspections in the Dallas regional office and 
Ruth Ann Dorrill, Deputy Regional Inspector General.  
Amy Ashcraft and Jeremy Moore served as team leaders for this study.  Other 
principal Office of Evaluation and Inspections staff from the Dallas regional 
office who contributed to the report include Maria Balderas and Nathan Dong.  
Central office staff who provided support include Heather Barton, Mandy Brooks, 
Evan Godfrey, Althea Hosein, and Joanne Legomsky. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Adverse Events in Inpatient Rehabilitation Facilities (OEI-06-14-00110)  35 
 
   
Office of Inspector General
http://oig.hhs.gov  
 
The mission of the Office of Inspector General (OIG), as mandated by Public Law 95452, 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 individuals 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 individuals.  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 OIGs  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.