The value of benefit data in direct-to-consumer drug ads.

Direct-to-consumer (DTC) pharmaceutical ads typically describe drug benefits in qualitative terms; they rarely provide data on how well the drug works. We describe an evaluation of a "prescription drug benefit box"-data from the main randomized trials on the chances of various outcomes with and without the drug. Most participants rated the information as "very important" or "important"; almost all found the data easy to understand. Perceptions of drug effectiveness were much lower for ads that incorporated the benefit box than for ads that did not. Most people we interviewed want benefit data in drug ads, can understand these data, and are influenced by them.