Reporting of Adverse Drug Events: Examination of a Hospital Incident Reporting System

Background: Voluntary hospital reporting systems are potentially valuable sources of information about medical errors and adverse events. This study examined the extent and variation in the reporting of medication errors and adverse drug events in a voluntary hospital incident reporting system. Methods: A retrospective analysis of received incident reports of potential and preventable adverse drug events over a 22-month period was conducted at a 1,300-bed, university-affiliated, tertiary care hospital. Reporting of adverse drug events into the hospital’s online Risk Management Event/Incident Entry System (RMEES), which is mainly used by nurses, was compared to reporting by pharmacists into a pharmacy reporting system (PHRED). Results: During the study period, the reported preventable and potential adverse drug event rates were 0.47 and 1.85 per 1,000 patient days, respectively, for RMEES-reported events compared with rates of 0.08 and 41.5 per 1,000 patient days for PHRED-reported events. Significant differences by service (P < 0.001) were present for potential adverse drug event rates in both RMEES and PHRED, but preventable adverse drug event rates did not differ significantly (P > 0.05) by service. A modest relationship (R = 0.27) between potential and preventable adverse drug event rates reported to RMEES was present. The median ratio of potential to preventable adverse drug events in RMEES was 4.5 (range = 0 to 16). The median ratio of PHRED to RMEES reports was 7.8, but varied markedly among individual nursing units (range = 0 to 157). Conclusions: Compared with rates reported in the literature, voluntary incident reporting yielded a much lower reporting rate of adverse drug events with considerable variation in reporting among units and service areas. Voluntary reporting of medical errors and adverse events is unlikely to yield reliable estimates of event rates. Introduction Hospitals and health care providers strive to deliver the safest care possible. Nevertheless adverse drug events are common, often preventable, and costly. Preventable adverse drug events occur due to medication errors, which include errors in the process of ordering or delivering a medication and errors of omission (e.g., failing to administer a drug as prescribed). Bates et al. 17 estimated that approximately 1 percent of medication errors result in adverse drug events. Minimizing or eliminating medication errors is vital to improve patient Advances in Patient Safety: Vol. 1 146 safety and the quality of hospital care. Medication error reporting is an essential component of achieving these goals. Several national voluntary and mandatory reporting systems exist for medication errors, adverse events, and medical device problems in the United States. The Institute of Medicine called for national mandatory reporting to State departments of health of events that result in death or serious harm, and voluntary reporting within health care organizations of less serious events. 23–27 The Institute for Safe Medical Practices, however, has endorsed voluntary reporting of adverse drug events. 24, 26 Although the debate regarding the need for voluntary or mandatory reporting systems continues, 28–32 voluntary reporting systems are more appealing to institutions and are potentially valuable sources of information that hospitals could use for systemwide improvements. Previous research on voluntary incident reporting involved examining reports on a restricted number of patient care units for limited time periods, typically less than 1 year. To better understand how to enhance incident reporting, it is essential to examine the existing state of reporting, particularly voluntary systems. This study analyzed a hospitalwide voluntary incident reporting system at an academic teaching hospital during a 22-month time period. Specifically, this study aimed to determine the extent and variation in the reporting of potential and preventable adverse drug events by comparing incident reporting with other information sources, such as pharmacist reporting of events.