Prevention of prescription errors by computerized, on-line surveillance of drug order entry.

Aims: The present study was undertaken to quantify the impact of computerized drug order entry system (CDOE) connected to the patients' database, on the incidence and type of prescription errors (PEs) in the medical service, and to delineate the causes for remaining errors.

Methods: Drug orders were reviewed daily by a physician-reviewer, in a department of internal medicine that used for more than 3 years a CDOE (CDOEdept), and in a similar department in which drug orders were handwritten (HWdept). PEs were divided into those not related to the individual patient (type 1 PEs), and PEs resulting from drug-laboratory, drug-disease, and drug-allergy interactions (type 2 PEs).

Results: Ten thousand and two hospitalization days were evaluated. The incidence of type 1 PEs was 5.21 and 1.36 per 100 hospitalization days in the HWdept and CDOEdept, respectively (p<0.0001). Type 2 PEs were more common, 7.20 and 3.02 per 100 hospitalization days in the HWdept and CDOEdept, respectively (p<0.0001), and about 75% of them were due to few drug-laboratory interactions. Most of the remaining errors in the CDOEdept were due to inadequate adjustment of drugs and doses to renal function, or failure to perform adequate changes when new laboratory results became available.

Conclusions: We conclude that linking the CDOE with few, specific, laboratory results has a large impact on the prevention of PEs. Combining the CDOE with a drug-laboratory alert system is expected to further reduce the incidence of PEs.