An empirical typology of seriously and persistently mentally ill patients using symptom and social functioning factors.

This study generated an empirical, statistically based typology that used both symptom data and social functioning dimensions to define subtypes of seriously mentally ill patients. The intent of using social functioning information was to explore the degree to which it improves clinicians' understanding of and treatment planning for diverse subgroups of patients. Social functioning dimensions and symptom data collected on a group of SPMI (seriously and persistently mentally ill) patients were factor analyzed and then submitted to a cluster analysis that yielded five meaningful patient subtypes. Demonstrations of the usefulness of this classification included significant subgroup differences on clinically important external variables, including needs for specific types of treatment and service consumption. For comparison purposes, the failure of the DSM-III diagnostic classification to distinguish patients on the clinically relevant criteria also was demonstrated.