OFfICE O}" INSPECTOR (;l~NEllAL 

JUL 1 9 2012 

TO: 	 Marilyn Tavenner 

Acting Administrator 

Centers for Medicare & Medicaid Services 

FROM: Stuart Wright 

Deputy Inspector General 

for Evaluation and Inspections 

SUBJECT: 	 Memorandum Report: Few Adverse Events in Hospitals Were Reported to 

State Adverse Event Reporting Systems, OEI-06-09-00092 

This memorandum report provides information requested by officials of the Centers for 

Medicare & Medicaid Services (CMS) about hospital reporting of adverse events to State 

reporting systems. The Office of Inspector General (OIG) collected this information 

while conducting a 2001- 2012 series of studies about adverse events in hospitals. 

SUMMARY 

Previous ora work found that an estimated 27 percent of Medicare beneficiaries 

hospitalized in October 2008 experienced harm from medical care, either serious adverse 

events (defined as events resulting in prolonged hospitalization, permanent disability, 

life-sustaining intervention, or death) or temporary hann events (defined as events 

requiring intervention but not resulting in lasting harm). To determine this rate of 

adverse and temporary harm events (referred to collectively as events), we examined 

medical records for a nationall.y representative sample of 780 hospitalized Medicare 

beneficiaries in October 2008. Prior OIG work also found that in 2008, about half of 

States operated adverse event reporting systems to monitor the occurrence of events in 

hospitals. Typically, these States required hospitals to report only specific types of 

events and analyzed the events in aggregate. This memorandum extends our prior work 

by providing national estimates for the extent to which events experienced by Medicare 

beneficiaries occurred in States that operated adverse event reporting systems, whether 

States required reporting of the identified events, and whether the hospitals reported the 

events to the State systems. 

We found that an estimated 60 percent of adverse and temporary harm events nationally 

occurred at hospitals in States with reporting systems, yet only an estimated 12 percent of 

events nationally met State requirements for reporting. We also found that hospitals 

reported only 1 percent of events. Most of the events that States required to be reported, 

but that hospitals did not report, were not identified by internal hospital incident reporting 

systems. This suggests that low reporting to State systems is more likely the result of 

hospital failure to identify events than from hospitals neglecting to report known events. 
 

 

 

 

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BACKGROUND 

Adverse Events in Hospitals 

Beginning in 2008, OIG released a series of reports regarding adverse events in hospitals. 

For the report Adverse Events in Hospitals: National Incidence Among Medicare 

Beneficiaries, we conducted a physician review of medical records for a nationally 

representative sample of 780 Medicare beneficiaries hospitalized in October 2008. We 

found that an estimated 13.5 percent of hospitalized Medicare beneficiaries experienced 

adverse events. An additional 13.5 percent of beneficiaries experienced temporary harm 

events.1 

For the report Hospital Incident Reporting Systems Do Not Capture Most Patient Harm, 

we determined whether the 189 hospitals where these events occurred had identified the 

events through their internal incident reporting systems. We found that all the hospitals 

had incident reporting systems designed to capture staff reports regarding adverse events, 

yet hospital staff reported only 14 percent of events experienced by Medicare 

beneficiaries.2 Hospital administrators indicated that staff often did not report events 

because they identified them not as patient harm, but rather as expected side effects. 

State Adverse Event Reporting Systems 

In the 2008 report Adverse Events in Hospitals: State Reporting Systems, we found that 

25 States and the District of Columbia (hereinafter referred to as 26 States) operated 

systems to collect adverse event data submitted by hospitals.3

 All these State systems 

received event descriptions and hospital names, but varied as to whether they made 

reporting voluntary or mandatory, what types of events they specified should be reported, 

and what additional information they asked hospitals to report. Most State systems 

required hospitals to report a subset of adverse events, usually serious events resulting in 

permanent disability or death, and events likely to affect the broader hospital population, 

such as infections. To date, no Federal standards require States to operate adverse event 

reporting systems. 

States with adverse event reporting systems used the reported information both to hold 

hospitals accountable and to promote learning about adverse events. Twenty-three of the 

twenty-six States with reporting systems routinely investigated reported events. 

Additionally, 18 of the 26 States used event reports to provide patient safety information 

and educational tools to hospitals, including the State incidence of adverse events, early 

warnings of new or widespread threats to patient safety, and analysis of contributing 

factors.4 

1

 OIG, Adverse Events in Hospitals: National Incidence Among Medicare Beneficiaries, 

OEI-06-09-00090, November 2010. 2

 OIG, Hospital Incident Reporting Systems Do Not Capture Most Patient Harm, OEI-06-09-00091, 

January 2012. 3

 OIG, Adverse Events in Hospitals: State Reporting Systems, OEI-06-07-00471, December 2008. 4

 Ibid. 
 

 

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METHODOLOGY 

We reviewed State policies to determine which events identified in our previous study 

were ones that States required hospitals to report. We then collected any reports about 

these events that hospitals sent to States. Based on the national random sample of 

hospitalized Medicare beneficiaries, we projected rates for the following: events 

experienced by Medicare beneficiaries that occurred in States that operated adverse event 

reporting systems in 2008 and events that these States required hospitals to report to the 

State systems. Appendix A contains estimates and confidence intervals for these 

statistics. We also determined which events hospitals reported to these State systems. 

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. 

RESULTS 

Although half of States operated adverse event reporting systems in 2008, only 

12 percent of events met State requirements for reporting 

An estimated 60 percent of adverse and temporary harm events nationally occurred at 

hospitals in States with reporting systems, yet only an estimated 12 percent of events 

nationally met State requirements for reporting. Of the events that States required to be 

reported, over half occurred in Pennsylvania, which required reporting of all events 

regardless of severity.5

 Table 1 breaks down the events by whether they were required to 

be reported to State systems. 

Table 1: Percentage of Hospital Events, by State and Whether State Required 

Event to be Reported 

Whether State Required Event to be Reported Percentage of All Events 

Event Occurred in State With Adverse Event Reporting System 60%

 Event did not meet State reporting requirements 49%* 

 Event met State reporting requirements 12%* 

Event Occurred in State Without Adverse Event Reporting System 40% 

Total Events 100% 

Source: OIG analysis of the 293 information requests completed by hospitals where events occurred. 

* Percentages do not sum to 60 percent because of rounding. 

Hospitals reported very few sampled events that States required to be reported 

Within our sample, hospitals reported only 3 of the 35 events required to be reported to a 

State reporting system. All 3 of these reported events occurred in Pennsylvania, which 

had a total of 22 events among sampled beneficiaries Statewide. All three of the reported 

events caused temporary harm to beneficiaries and were of types commonly targeted by 

hospital patient safety efforts (allergic reaction, fall, and pressure ulcer). 

5

 Pennsylvania: 40 P.S. § 1303.313. 
Page 4 – Marilyn Tavenner 

Nearly all unreported events also went undetected by internal hospital incident reporting 

systems. Of the 32 events that hospitals did not report to State systems as required, 

hospitals identified only 1 event within an internal incident reporting system. For the 

remaining 31 events, hospitals had no record indicating that staff recognized the event 

had occurred. This suggests that the low rate of reporting to State adverse event reporting 

systems is due largely to hospital staff not identifying incidents of harm as reportable 

events. 

Many of the events not reported to State systems as required involved serious harm to 

hospitalized Medicare beneficiaries. Six of the thirty-two events contributed to patient 

death, including cases involving lack of patient monitoring and missed diagnoses. For 

example, one patient death was the result of acute renal failure caused by the hospital not 

recognizing and treating a serious systemic inflammatory response syndrome 

(bacteremia). Another patient death was the result of poor insulin management escalating 

to a hypoglycemic coma. Other unreported events required the use of life-sustaining 

interventions, indicating that hospital staff were clearly alerted to a problem but still did 

not report the events. 

Further, the less serious, temporary harm events that hospitals did not report included 

many events that can become serious if not ameliorated, such as excessive bleeding and 

intravenous volume overload. The treatment required to stop the progression of these 

events also implies that in each case, hospital staff were likely aware of the patient’s 

condition but did not perceive the condition as an event. 

Table 2 lists the events in our sample that States required to be reported to adverse event 

reporting systems, whether hospital staff reported these events to incident reporting 

systems within the hospitals, and whether the events were reported to the State systems. 
 

 

 

 

 

 

 

 

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Table 2: Adverse Events That Required Hospital Reporting to State Adverse 

Event Reporting Systems (n=35) 

State Type of Event Level of Harm Reported 

within Hospital 

Reported to 

State System 

CA Excessive bleeding Contributed to death 

CO Blood stream infection Contributed to death 

IN Fall Prolonged hospital stay 

IN Pulmonary embolism Prolonged hospital stay 

KS Excessive bleeding Contributed to death 

MD Excessive bleeding Prolonged hospital stay • 

MD Excessive bleeding Prolonged hospital stay 

MD Hypoglycemic coma Life-sustaining intervention 

MD Hypotension Prolonged hospital stay 

MD Catheter infection Prolonged hospital stay 

NJ Excessive bleeding Contributed to death 

NJ Hypoglycemic coma Contributed to death 

NY Blood stream infection Contributed to death 

PA Acute renal failure Temporary harm 

PA Acute renal failure Permanent harm 

PA Allergic reaction Temporary harm • • 

PA Allergic reaction Temporary harm 

PA Congestive heart failure Prolonged hospital stay 

PA Dysrhythmia Temporary harm 

PA Excessive bleeding Temporary harm 

PA Excessive bleeding Temporary harm 

PA Fall Temporary harm • • 

PA Nausea and vomiting Temporary harm 

PA Pressure ulcer Temporary harm • • 

PA Pulmonary embolism Prolonged hospital stay 

PA Sepsis Life-sustaining intervention 

PA Skin tear Temporary harm 

PA Surgical tear Temporary harm 

PA Urinary retention Temporary harm 

PA Urinary tract infection Permanent harm 

PA Intravenous volume overload Prolonged hospital stay 

PA Intravenous volume overload Temporary harm 

PA Intravenous volume overload Temporary harm 

PA Intravenous volume overload Temporary harm 

TN Acute renal failure Prolonged hospital stay 

Source: OIG analysis of information provided by hospitals regarding 293 identified events, 2011. Level of harm from the National 

Coordinating Council for Medication Errors Reporting and Prevention Index for Categorizing Errors, Press Release, Medication 

Errors Council Revises and Expands Index for Categorizing Errors: Definitions of Medication Errors Broadened, June 12, 2001. 

CONCLUSION 

Although half of States operated adverse event reporting systems in 2008, hospitals 

reported few events to State systems. For all but one event that was not reported to State 

systems as required, the hospitals did not identify the events within internal incident 

reporting systems. This indicates that low reporting to State systems is more likely to 

result from hospital failure to identify events than from hospitals’ neglecting to report 

known events. CMS, States, and other stakeholders should be aware of this low rate of 

reporting to State systems as they consider strategies to reduce adverse events in 

hospitals. 

This report is being issued directly in final form because it contains no recommendations. 

If you have comments or questions about this memorandum report, please provide them 

within 60 days. Please refer to report number OEI-06-09-00092 in all correspondence. 
 

 

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APPENDIX A 

Estimates and Confidence Intervals 

We computed estimates and corresponding 95-percent confidence intervals using 

appropriate statistical methods based on the sample. 

Table A: Hospital Adverse Events and State Reporting (n=293) 

Adverse Event Point 

Estimate 

95-Percent 

Confidence Interval 

Lower 

Bound 

Upper 

Bound 

Event Occurred in State With Event Reporting System 60.4% 52.5% 67.8%

 Event did not meet State reporting requirements 48.5% 40.9% 56.1%

 Event met State reporting requirements 12.0% 8.2% 17.2% 

Event Occurred in State Without Event Reporting System 39.6% 32.2% 47.5% 

Total Events 

Source: OIG analysis of the 293 information requests completed by hospitals where events occurred.