Services research outcomes study: Explanation of treatment effectiveness, using individual-level and programmatic variables

This article examines the explanatory power of programmatic and individual- level variables, using the first nationally representative sample of both t reatment facilities and clients. Multivariate statistical models accounted for almost half the variance in posttreatment heroin, marijuana, and any il licit drug use and about one-third the variance in crime. Use of any illici t drug during treatment, even after controlling for pretreatment use, was p redictive of every type of drug use after treatment and three of the four m ajor crimes analyzed. In addition, longer lengths of stay decreased the lik elihood of alcohol/illicit drug use and criminal behavior after treatment. However, treatment variables added little explanatory power beyond the soci odemographic and pretreatment variables.