This family of studies is designed to provide comprehensive information on continuing and new questions about the effectiveness of the drug-abuse treatment that is available in a variety of publicly funded and private programs. These data update and augment the information available from earlier national studies, such as the DRUG ABUSE REPORTING PROGRAM (DARP) study, which began in the late 1960s, and the TREATMENT OUTCOME PROSPECTIVE STUDY (TOPS) of clients entering treatment in the 1970s. The work was sponsored by the NATIONAL INSTI-TUTE ON DRUG ABUSE (NIDA) and conducted by the National Development and Research Institute, Texas Christian University, and the University of California, Los Angeles.

The major objective of DATOS is to examine the effectiveness of drug-abuse treatment by conducting a multisite, prospective clinical and epidemio-logical longitudinal study of drug-abuse treatment. Effectiveness was examined by using data...