Incidence of clinically relevant medication errors in the era of electronically prepopulated medication reconciliation forms: a retrospective chart review.

Background: To reduce medication discrepancies (unintended differences between a patient's outpatient and inpatient medication regimens), Canadian institutions have implemented medication reconciliation forms that are prepopulated with outpatient medication dispensing data. These may prompt prescribers to reorder discontinued medications or continue newly contraindicated medications. Our objective was to evaluate the incidence of medication discrepancies and errors of commission after the implementation of such forms.

Methods: This retrospective chart review included patients previously enrolled in an observational study in which a research pharmacist prospectively collected best-possible medication histories in the emergency department. Research assistants uninvolved with the parent study compared medication orders written in the first 48 hours after admission with the research pharmacist's best-possible medication history to identify medication discrepancies and errors of commission, defined as inappropriate medication continuations and reordering of previously stopped medications. An independent panel adjudicated the clinical significance of the errors.

Results: Of 151 patients, 71 (47.0% [95% confidence interval (CI) 39.2-54.9]) were exposed to 112 medication errors on admission. Of the 112 errors, 24 (21.4% [95% CI 14.9-29.9]) were clinically significant. Errors of commission accounted for 24.1% (27/112 [95% CI 17.3-32.8]) of all errors; 10 (37.0% [95% CI 18.8-55.2]) of the errors of commission were clinically significant.

Interpretation: Medication errors were common after the implementation of electronically prepopulated medication reconciliation forms. Prospective research is required to examine the impact of prepopulated medication reconciliation forms and ensure they do not facilitate errors of commission.