Do drug samples influence resident prescribing behavior? A randomized trial

The purpose of the study was to determine whether access to drug samples influences resident prescribing decisions.

The authors observed 390 decisions to initiate drug therapy by 29 internal medicine residents over a 6-month period in an inner-city primary care clinic. By random selection, half of the residents agreed not to use available free drug samples. Five drug class pairs were chosen for study prospectively. Highly advertised drugs were matched with drugs commonly used for the same indication that were less expensive, available over-the-counter, or available in generic formulation.

Resident physicians with access to drug samples were less likely to choose unadvertised drugs (131/202 decisions) than residents who did not have access to samples (138/188 decisions; P = .04) and less likely to choose over-the-counter drugs (51/202, 73/188; P = .003). There was a trend toward less use of inexpensive drugs.

Access to drug samples in clinic influences resident prescribing decisions. This could affect resident education and increase drug costs for patients.