Effect of an automated bedside dispensing machine on medication errors.

The effect of an automated bedside dispensing machine on medication errors was studied on a 32-bed surgical unit of an 848-bed hospital. The experimental system (McLaughlin Dispensing System) included at each patient's bedside a locked medication cabinet that was electronically programmed to allow the nurse access to doses due at a particular time. The control system was a decentralized unit dose system. A crossover study design with random assignment of subjects and treatments was used. In the 14-day study period, nurses were observed by a pharmacist for 28 five-hour periods as they administered medications on the day and evening shifts. The mean error rates were significantly different--10.6% for the experimental system and 15.9% for the control system. Wrong time errors were the most common type. No significant differences were found between day and evening shifts or workloads of individual nurses. There was no treatment order effect. The error rate was significantly lower for the automated dispensing system than for the system using unit doses dispensed from a satellite pharmacy. Automated dispensing systems may be useful in reducing errors in administration time and dose omissions.