Influence of computerised medication charts on medication errors in a hospital

In hospitals where computerised physician order entry systems will not be available in the near future, there is a need to explore other ways of reducing medication errors that occur in the drug ordering and delivery system. One of these ways is the use of a computerised medication chart that is updated daily. The aim of this study was to evaluate the frequency, types and potential clinical significance of drug prescription and administration errors by comparing a traditional medication distribution system (where the transcription of handwritten into printed medication orders takes 3-5 days and the transfer of medication orders was not complete) with the use of a computerised medication chart (which was updated daily by pharmacy assistants on the ward).

Data were collected during two 3-week periods, from a 32-bed internal medicine unit, before and after the introduction of the computerised medication charts. Prescribing errors were observed by evaluation of all new and changed medication orders and administration errors were detected by using the disguised-observation technique.

For prescribing errors, a total of 611 prescriptions before and 598 prescriptions after the intervention were evaluated. The total prescription error rate (of medication orders with >or=1 error) was found to be significantly higher with the computerised charts when compared with the old system (50.0% [299 of 598] vs 20.3% [124 of 611], odds ratio [OR] 3.80 [95% CI 2.94, 4.90]). This increase was caused by an increase in administrative prescription errors with a low potential clinical significance (mainly omission of the prescriber's name and the prescription date). The error rate for errors with a potential clinical significance was found to be significantly lower because the prescription error 'duplicate therapy' was eliminated (3.4% with the traditional medication chart vs 0% with the computerised chart). For administration errors, a total of 1122 drugs before the intervention and 1175 drugs after the intervention was observed to be administered. The total administration error rate was found to be significantly lower after the intervention (6.1% [72 of 1175] vs 10.5% [118 of 1122], OR 0.61 [95% CI 0.45, 0.84]), as was the error rate with a potential clinical significance. The contribution of handwritten medication orders to the total amount of medication orders was significantly decreased after the intervention (12.8% vs 20.6% [95% CI 4.6, 11.0]) and the administration of a drug ordered by a handwritten medication order resulted in a significantly higher administration rate than with administration of a drug ordered by a printed medication order (before the intervention 20.7% vs 8.0%, OR 2.99 [95% CI 1.96, 4.56], after the intervention 11.4% vs 5.6%, OR 2.18 [95% CI 1.16, 4.11]).

This observational study shows a significant reduction in clinically relevant, administration and (therapeutic) prescription error rates when applying a system using computerised and daily updated medication charts compared with a system using traditional medication charts. Therefore, the use of computerised and daily updated medication charts has the potential to improve the quality of the medication distribution process in hospitals waiting for the implementation of a computerised physician order entry system.