Control charts to monitor rates of adverse drug reactions.

We describe the use of control charts in monitoring rates of adverse drug reactions. Adverse drug reactions are recognized as important outcomes of patient care and are specifically associated with the process of medication use. The systematic monitoring of adverse drug reactions may allow one to identify opportunities to improve this process. Reported adverse drug reactions from 36 consecutive months at a university hospital were analyzed. The mean rate of adverse drug reaction reporting was 1.65% (denominator of patient admissions) and the 3 sigma upper and lower control limits were 3.22% and 0.08%, respectively. The mean rate of preventable adverse drug reactions was 21.25% (denominator of total reported adverse drug reactions) and the 3 sigma upper and lower control limits were 73.54% and < 0%, respectively. The experience described in this report suggests that monitoring adverse drug reactions using control charts, facilitates identification of trends in reporting and the actual incidence of adverse drug reactions, and allows identification of opportunities to improve the systems and processes of medication use.