Evaluating the impact of information technology on medication errors: a simulation.

Information technology has been shown to reduce med- ication errors and associated ADEs at every stage in med- ication administration. 1 Information systems include deci- sion support at the prescription stage, computerized physician order entry, unit dosing systems, and bar-cod- ing of individual medications among others. We devel- oped a computer simulation model and used it to evalu- ate the effectiveness of a number of information technolo- gy applications, individually and collectively, to reduce medication errors and associated ADEs. 2 The model incor- porated estimates from published studies of the potential reduction in medication errors that could result from implementation of various information technologies. Shojania questions two of these estimates, specifically potential reductions in errors from implementing bar- coding and unit dosing. We assumed that bar-coding medications potentially could reduce drug administra- tion errors by as much as 60%. This estimate is support- ed by other studies. Puckett 3 reports on the effect of the introduction of CliniCare, a point-of-care information system for medication management, in a primary and tertiary care center. All medications were bar-coded and scanned at or near the patient's bedside. He reports a medication error rate of 0.17% before implementation of the system. In the following year the medication error rate dropped by 59% to 0.07% and during the next year to 0.05%, a 70% decrease. We estimated that the introduction of a unit dose system could reduce errors by as much as 80%. Unit dose sys- tems dispense most medications from the pharmacy in a ready-to-administer form and are widely used in U.S. hospitals. Studies that have evaluated the impact of unit- dose dispensing on medication errors report reduction in medication error rates ranging from 53% to 85%. 4-7 However, as Shojania points out, other studies have demonstrated mixed results from implementing some of these technologies. For example, an ethnographic study of the implementation of bar-code medication administration (BCMA) in several hospitals, while not reporting medication error rates before and after imple- mentation, found several side effects that created the potential for new ADEs. 8 Moreover, we do not know for certain how much of a reduction in error rates is associated with implementing unit dose and bar code systems in hospitals. This uncer- tainty is due to the limited number of studies, varied definitions and methodologies that have been used in the studies that have been performed, and the small number of institutions involved in these studies, mak- ing any one study subject to local and regional varia- tions in providers, patient populations, etc. As a result we reran estimates of the cost savings that could be expected from an integrated medication system that included unit dosing and bar-coding of medications assuming that error reductions resulting from these two applications would only be in the order of 40% and 30%, respectively. We estimated potential savings of over $820,000 even with the lower rates, a significant impact of these interventions.