THE USE OF ARCHIVAL DATA TO SELECT AND ASSIGN SCHOOLS IN A DRUG PREVENTION TRIAL

School-based prevention trials typically face large variations in school composition and levels of preintervention behavior. Such variations may inhibit efforts to maximize internal and external validity. This article presents a method for using school-level attributes in sample description and random assignment of schools to conditions. The utility of the archival data was examined using multivariate canonical techniques. The authors found that a small set of attributes could efficiently predict the observed school-level variations in smoking and other drug use. It is recommended that these attributes be used by other school-based studies to enhance experimental field studies.