drug withdrawal. In the case of methadone maintained, opiate dependent patients, studies by McLellan and colleagues (1983a,b) indicated that the psychiatric severity scale from the Addiction Severity Index was the single best predictor of six month substance use, personal health, and social adjustment. Similar findings have been shown by Ball and Ross (1991) and by Kosten and colleagues (1987) and Rounsaville and colleagues (1983, 1987) with methadone maintained patients.
Measures of psychiatric severity have also been shown to be predictive of outcome in studies of opiate and multiple drug dependent patients entering an inpatient therapeutic community setting. For example, De Leon (1984) showed that opiate and non-opiate dependent patients with MMPI profiles indicative of high levels of psychopathology entering a therapeutic community were more likely to drop out of treatment and showed significantly less improvement on all outcome measures at discharge and at subsequent twelve month follow-up evaluations. In an earlier study of mixed opiate and non-opiate dependent male veterans entering into a therapeutic community McLellan and colleagues (1984) found that patients with the highest scores on the ASI psychiatric severity scale were most likely to drop out prematurely and actually showed 20%-40% less improvement than other patients who entered treatment at the same time. In that study, the "high psychiatric severity" patients who stayed in treatment longest actually showed the worst posttreatment status—suggesting that the therapeutic environment that had been demonstrably effective for patients with lower levels of psychiatric severity, was actually counter therapeutic for the high severity patients.
In the case of cocaine dependent patients, Carroll et al. (1991) also found poorer outcomes for patients with greater psychiatric pathology, as defined by scores on the Addiction Severity Index (ASI) psychiatric problem scale. Her findings were obtained in an outpatient rehabilitation setting. Similar results were found among cocaine dependent patients by Alterman et al. (1994) for patients treated in both a day-hospital and an inpatient rehabilitation setting.
Finally, there has been a great deal of evidence for the predictive power of general psychiatric symptomatology among alcohol dependent patients. Rounsaville and colleagues showed that psychiatric severity as measured by the ASI psychiatric scale was the best predictor of overall adjustment among previously treated alcohol dependent patients at a 2.5 year posttreatment follow-up (Rounsaville et al., 1987). Other authors have found that severity of depression (Powell et al., 1982; Schuckit et al., 1990) and anxiety (Brown et al., 1991; Schuckit et al., 1990) have been predictive of posttreatment drinking and posttreatment social adjustment among various samples of alcohol dependent patients. More recently, findings from the NIAAA sponsored, multisite study of patient treatment matching (Project MATCH,