Challenges in measuring antibiotic consumption.

The measurement of antibacterial consumption is important for tracking use over time, for assessing correlations between use and antibacterial resistance, and for serving as an outcome measure for antimicrobial stewardship programs. Accurate and consistent measures of use are important for meaningful inter- and intrainstitutional comparisons. The defined daily dose (DDD) and days of therapy methods are commonly used measures in the adult population; however, there is no one ideal measure of consumption that covers the breadth and depth of antibacterial prescribing. The use of the DDD and the prescribed daily dose methods, with further stratification of use by weight and age groups, aids in the evaluation of antimicrobial use in pediatric patients. Increasing availability of computerized pharmacy data should enhance the collection and analysis of data from hospitals.