The impact of antibiotic management on resistance.

The misguided presumption that a simple inverse relationship exists between the use of antibiotics and the emergence of bacterial resistance (i.e., increasing antibiotic use equals decreasing susceptibility and vice versa) has handicapped a full understanding of this relationship and perhaps efforts to bring resistance under control. In fact, this relationship is complicated. This article reviews factors that obscure detection of associations between antibiotic use and the emergence of resistance. It also provides a sample of the extensive data on this subject in the hope of encouraging the conduct of more sophisticated studies of the relationship between antibiotic use and the emergence of resistance. Such studies are necessary to provide institutions with the data they need to make informed decisions regarding antibiotic use.