“…The inconsistent findings that have emerged in this literature may be due to the fact that outcome research in the area of substance abuse treatment has suffered from various methodological shortcomings (Howard & McCaughrin, 1996; Rotgers, 1992; Shearer, 2000). These include differences in outcome measures (e.g., measuring recidivism rates rather than client drinking levels, measuring employee job performance rather than level of substance use) and differences in comparison groups (e.g., comparing young, mandated, relatively healthy individuals with voluntary, older, chronic addicts).…”