has not been replicated, and future research will be needed to test these effects in samples more generalizable to the recent literature on substance abuse in SMI. Third, there may be concerns about our use of the DSM-III-R [43]. We found few differences existed between the DSM-III-R and the DSM-IV-TR criteria [43–45]. Given that DSM-III-R criteria were rigorously applied, and confirmed by the DSM-III-R checklist [39], we do not believe that our use of the DSM-III-R has markedly restricted the applicability of this research. It should also be noted that our use of the GAF to assess functional outcomes is limited because of its global focus and its incorporation of symptomatology into the measurement [43]. Since information on treatment and medication compliance were not systematically collected [37], it will be important for future research to examine the potentially confounding effects of these factors. Lastly, we can only comment on the differences observed during the course of 1-year, and future longitudinal research will need to be conducted in this population.
