Year: 2006 Source: Clinical Trials, v.3, no.3, (2006), p.259-271 SIEC No: 20060943

This paper examines a new class of statistical designs where random assignment to intervention condition occurs at multiple times in a trial. As an example, the authors present a large ongoing trial to evaluate a gatekeeper training suicide prevention program in 32 schools which initially began as a classic randomized wait-listed design. A general result shows that dynamic wait-listed designs always have higher statistical power over a traditional wait-listed design. As with all wait-listed designs, dynamic wait-listed designs can only be used to evaluate short-term impact. (39 refs.)