The Project MATCH sample included a total of 1,726 patients divided into two groups: the Aftercare (n = 774) and Outpatient (n = 952) arms (Project MATCH Research Group, 1997). The majority of subjects were male (72% in the outpatient arm and 80% in the aftercare arm). In the outpatient sample, the mean age was 38.9 (SD = 10.7), and 80% were White, 6% were African American, and 12% were Hispanic. In the aftercare sample, the mean age was 41.9 (SD = 11.1), 80% were White, 15% African American, and 3% Hispanic. Many had been treated for alcohol problems prior to treatment (62% of outpatients and 45% of aftercare participants) and were unemployed at the beginning of the study (48% of outpatients and 51% of aftercare participants). Subjects in the outpatient arm were selected from outpatient centers in the community. Subjects in the aftercare arm were treated immediately following intensive inpatient or day-hospitalizations. Subjects were selected in this way to accommodate the ongoing practice of clinical research units to specialize in either outpatient or aftercare patients, and to increase the
