Abstract
Two experiments using physicians as subjects were conducted. All experiments manipulated the incentive to hysicians for completing a mailed survey. The results indicate that t 1 e level of monetary incentive and length of the questionnaire have a large effect on the return rate of a mailed questionnaire. Results further indicate that a questionnaire to ic of direct interest to the physician's specialty also results in a hig R er return rate. It is suggested that a social exchange process may be occurring when a questionnaire is completed.