Impact of Emerging Technologies on Medication Errors and Adverse Drug Events

Eyal Oren, Ellen R. Shaffer, B. Joseph Guglielmo


Am J Health Syst Pharm. 2003;60(14) 

In This Article


The search resulted in 103 studies, of which 92 were excluded (Appendix A). The 11 studies evaluating endpoints are summarized in Table 1 .[2,19,20,21,22,23,24,25,26,27,28] Of these 11, only 3 studies evaluated the impact of CPOE on medication errors and ADEs.[2,20,28] One study observed a reduction in both preventable and potential ADEs when a CPOE system was implemented.[20] The rates of nonintercepted serious medication errors (errors that are not intercepted before injury) and nonintercepted potential ADEs (errors that by chance resulted in no injury) were significantly reduced with CPOE. Furthermore, these reductions were observed across all levels of severity for nonintercepted serious medication errors. Specifically, dosage errors decreased by 23% and errors associated with known allergies fell 56%.

In another trial evaluating medication errors and ADEs, decreases in medication errors were observed with CPOE for all major categories of medication errors.[2] Medication errors were further categorized as "missed dose" and "nonmissed dose." The nonmissed dose medication error rate per 1000 patient-days decreased by 81%. The missed-dose error rate per 1000 patient-days climbed significantly with the use of CPOE. Reasons for the increased missed-dose errors were not documented; however, the authors indicated that changes in patient acuity, pharmacy staffing, and other workflow changes may have contributed. The authors suggested that each missed-dose error resulted in 15 minutes of extra work for nursing and pharmacy personnel. The nonintercepted serious medication error rate per 1000 patient-days also fell significantly.

Of the 11 studies evaluating the impact of CPOE, 9 took place at two institutions. Only one study was identified that evaluated our second aim, the appropriateness of use of CPOE, as well as the first aim, impact on patient outcomes.[28] Regarding the first aim, the study assessed a computerized disease-management program that provided patient-specific information at the time of order entry. The number of ordered antiinfective agents decreased, the duration of therapy was reduced, the cost of antiinfectives decreased, and the length of hospital stay was reduced. Adverse events caused by antiinfectives decreased compared with the preintervention period.

Appropriate use of CPOE was also addressed.[28] In this CPOE system, the physician could electively bypass, i.e., override, the system. CPOE was overridden by physicians approximately half the time. When CPOE was overridden, the mean number of prescribed agents increased from 1.5 to 2.7, the duration of therapy increased from 103 to 330 hours, the mean number of doses increased from 11.4 to 27.6, the mean cost of agents increased from $102 to $427, and the mean length of stay climbed from 10.0 to 16.7 days.

The search resulted in 30 studies. Of these, 23 were excluded (Appendix B). Seven controlled studies evaluating primary or secondary controlled endpoints were included ( Table 2 ).[29,30,31,32,33,34,35] Five of these studies evaluated medication errors and ADEs, and two assessed secondary endpoints. One study identified a reduction in the number of medication errors (97/929 [10.4%]) with the ADM compared with the control (148/873 [16.9%]) (p < 0.001).[30] Fewer wrong-time errors occurred after ADM implementation, which accounted for the greatest percentage of all errors. The rates of other types of errors were unchanged or decreased after ADMs were implemented. Other investigators observed a reduction in medication errors associated with ADMs in a cardiovascular surgery unit but an increase in an intensive care unit.[32] While significance was not reported, the number of reported medication errors increased by more than 30% in six of the seven nursing units evaluated. The types of medication errors observed were not reported. Significantly fewer missing doses were reported after ADM implementation.

No controlled studies demonstrating appropriateness of use were found.

The search resulted in 46 studies. Of these, 39 were excluded (Appendix C). Seven controlled studies were included that evaluated primary and secondary endpoints related to the first aim regarding patient outcomes ( Table 3 ). Five studies assessed primary endpoints (medication errors and ADEs) and two looked at secondary endpoints.[36,37,38,39,40,41,42] After bar-code implementation, the error rate in an ambulatory care pharmacy decreased from 1.0% to 0.2%; stock-ordering times were also significantly reduced with the bar-code system.[36] Errors increased in the sterile products preparation area, largely because of misreading by the bar-code device.

Regarding the secondary endpoints, overall, fewer system errors and more efficient ordering resulted in a significant time reduction in workflow from the stockroom to the sterile products preparation area and ambulatory care pharmacy.

One study observed a significant reduction in medication errors associated with bar codes compared with a keyboard method.[38] The mean data-entry transaction times were not significantly different. In another prospective trial, emergency-room nurses viewed videotapes of resuscitations of four trauma patients, then recorded the actions taken during each resuscitation either by handwritten entry or by bar-code entry.[40] The mean ± S.D. number of errors per record with bar codes was 2.63 ± 0.24, compared with 4.48 ± 0.30 for handwritten entry. The total number of omission errors and inaccuracy errors decreased, as did the number of omissions and number of inaccuracies per record.

No studies demonstrating appropriateness of use were found.

The search resulted in eight publications, five of which consisted of commentaries and letters and two overviews and guidelines (Appendix D). One study evaluated the impact of CMARs on the efficiency of medication delivery and administration, but we were unable to obtain the publication for review.[43]

The definitions of ADEs and medication errors used in the included studies are listed in Table 4 .


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.