Abstract
This investigation identified personality subgroups based upon cluster analysis of MMPI-2 records of polysubstance abus -ers. Subgroups were compared on lifetime and current psychiatric symptoms and on attitudes and behaviors linked with HIV infection risk. High psychopathology, mild psychopathology, and subclinical MMPI-2 cluster types were identified which resemble those that have been identified in earlier studies with the original version of the MMPI. The High Psychopathology Subgroup had significantly higher proportions with all lifetime psychiatric problems (ASI), higher levels of all current psychiatric symptoms (SCL-90), and lower levels of con -fidence in ability to enact safer sexual practices than the Subclinical Cluster Subgroup. Fewer differences in lifetime and concurrent psychiatric symptoms were found in comparisons involving High Pathology and Mild Pathology cluster subgroups and Mild Psychopathology and Subclinical cluster subgroups. Those in the High Psychopathology Subgroup likely need treatment programs that address their more chronic and serious mental health problems and inter -ventions that target their judgment and problem solving limitations that may increase HIV infection risk.