Computerized decision support for medication dosing in renal insufficiency: a randomized, controlled trial.

STUDY OBJECTIVE: Emergency physicians prescribe several discharge medications that require dosage adjustment for patients with renal disease. The hypothesis for this research was that decision support in a computerized physician order entry system would reduce the rate of excessive medication dosing for patients with renal impairment. METHODS: This was a randomized, controlled trial in an academic emergency department (ED), in which computerized physician order entry was used to write all prescriptions for patients being discharged from the ED. The sample included 42 physicians who were randomized to the intervention (21 physicians) or control (21 physicians) group. The intervention was decision support that provided dosing recommendations for targeted medications for patients aged 18 years and older when the patient's estimated creatinine clearance level was below the threshold for dosage adjustment. The primary outcome was the proportion of targeted medications that were excessively dosed. RESULTS: For 2,783 (46%) of the 6,015 patient visits, the decision support had sufficient information to estimate the patient's creatinine clearance level. The average age of these patients was 46 years, 1,768 (64%) were women, and 1,523 (55%) were black. Decision support was provided 73 times to physicians in the intervention group, who excessively dosed 31 (43%) prescriptions. In comparison, control physicians excessively dosed a significantly larger proportion of medications: 34 of 46, 74% (effect size=31%; 95% confidence interval 14% to 49%; P=.001). CONCLUSION: Emergency physicians often prescribed excessive doses of medications that require dosage adjustment for renal impairment. Computerized physician order entry with decision support significantly reduced excessive dosing of targeted medications.