Implementation of Residential and Nonresidential Treatment for the Dually Diagnosed Homeless

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. Fully 40% of subjects assigned to either treatmentfailed to become engaged for even one day, although a significantly higher percentage of those assigned to the residential program than the nonresidential program graduated from the first 3-month phase of treatment. The analysis revealed significant differences in the type and amount of services provided by the two treatment programs, as well as potentially important difficulties in program management. Such process data are valuable toolsfor understanding client outcomes and interpreting experimental results.