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Study shows value and limitations of voluntary error reporting systems

The Institute of Medicine, in its 1999 To Err is Human report, recommended that health care organizations establish medical error reporting systems. A team of researchers, led by Chunliu Zhan, M.D., Ph.D., of the Agency for Healthcare Research and Quality, conducted a study to explore the value and limitations of voluntary medical error reports, using common errors in warfarin use as a case study.

The researchers analyzed warfarin medication errors reported by hospitals and clinics participating in the MEDMARX voluntary medication errors reporting system. A total of 8,837 inpatient warfarin errors were reported by 445 hospitals from 2002 to 2004, ranging from 1 to 289 errors per hospital; 820 outpatient warfarin errors were reported by 192 outpatient facilities during that same period. The most common types of warfarin errors were related to dosing (select for chart).

The most commonly reported cause of errors in hospitals were prescription transcribing/ documenting (35 percent) and drug administering (30 percent) and in outpatient settings, drug prescribing (31 percent) and dispensing (39 percent). The causes of errors were often multiple. The most frequent cause was the failure to do what is known to be right, which is often related to a distracting work environment, heavy work load, and understaffing. Corrective interventions, therefore, need to be multidimensional, suggest the researchers.

They pointed out that voluntary reporting systems are limited by lack of details, incomplete reporting, underreporting, and various reporting biases; also, they cannot yield a true error rate. However, such systems nevertheless provide useful information to guide patient safety improvements. For example, in this study, 17 percent of inpatient and 13 percent of outpatient warfarin errors resulted in changes in patient care.

See "How useful are voluntary medication error reports? The case of warfarin-related medication errors" by Dr. Zhan, Scott R. Smith, Ph.D., Margaret A. Keyes, M.A., and others in the January 2008 Joint Commission Journal on Quality and Patient Safety 34(1), pp. 36-45.

Reprints (AHRQ Publication No. 08- R047) are available from the AHRQ Publications Clearinghouse.

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