Introduction: Studies which used the Psychopathy Checklist-Revised (PCL-R) among methadone maintenance treatment (MMT) patients focused mostly on methodological issues, without addressing its relationship to patients' misconduct during treatment. This paper tests the hypothesis that high PCL-R scores are related to high rates of drug abuse, and high numbers of behavioral transgressions in MMT during a 7-year period. Material and Methods: 107 MMT patients were recruited from a MMT clinic in Israel, and were administered the PCL-R. The questionnaires results as well as routine drug test findings were recorded between 7/2007 and 11/2007. Seven years later (7/2014), repeated drug test results were analyzed, and the number of behavioral transgressions during the entire period was computed. Results: High levels of psychopathy were related to drug test results indicating any illicit drug use, cocaine use and benzodiazepines misuse at the beginning of study, and limited to benzodiazepines misuse among patients who stayed in treatment at the 7-year follow-up. However, higher scores on different PCL-R facets were significantly associated with different types of drugs. The PCL-R's total score and all but the antisociality facet were positively correlated with a higher number of behavioral transgressions (such as, threats and/or verbal and physical aggression). Conclusions: Administration of the PCL-R during MMT may help identify patients with high illicit drug use levels and a higher chance of committing behavioral transgressions during treatment.
Keywords: MMT; PCL-R; behavioral transgressions; illicit drug use; psychopathy.