The common mistakes made in manual prescribing systems continue to turn up in electronic versions,results of a recent retrospective cohort study suggest.

The analysis focused on 3,850 computer-generated prescriptions received across three states over four weeks in 2008. In total, 452 prescriptions (11.7%) contained 466 errors, 163 (35%) of which were considered potential adverse drug events. None of the errors were life-threatening. Omitted information was the most common mistake, accounting for 60.7% of all errors.

Error rates varied among the 13 computerized prescribing systems evaluated, ranging from 5.1% to 37.5%. Certain errors were more frequently associated with a particular system. For example, users often failed to specify length of treatment and dose in one system. When two other systems were compared, one was linked with fewer errors overall than the other, but with more mistakes that were potentially harmful.

“Implementing a computerized prescribing system without comprehensive functionality and processes in place to ensure meaningful system use does not decrease medication errors,” cautioned Karen C. Nanji, MD, and coauthors in their report for Journal of the American Medical Informatics Association (published online ahead of print).

The researchers noted that the problem of missing information should be relatively easy to rectify through improved training for users or tweaks made to the system. One option involves “forcing functions,” which would not allow a prescription to be completed if certain data were not included.