An implementation analysis conducted as part of a 2-year experimental study of residential and nonresidential treatment programs for the dually diagnosed homeless found significant differ ences in client engagement and retention, as well as unexpected variations in the treatment conditions....

Young adults who had previously participated in a longitudinal survey of youth were sent a questionnaire. They were randomly assigned to receive a $20 prepayment, a $20 postpayment, or a $25 postpayment for participation in the latest survey. Those in the large incentive condition were 7...