Simple measures of case mix in mental health services.

The concept of Case Mix in community mental health service program evaluation can be useful in mental health program evaluation if the definition of case mix is expanded beyond Diagnostic Related Groups (DRG), where DRG is solely based upon diagnosis and length of hospitalization stay. A case mix definition based upon two principal characteristics is offered. One characteristic is clinical status defined in terms of diagnostic signs and symptoms, level of functioning, and age. The other characteristic is typical treatment strategy for a given period of time (e.g., 13 weeks). Two cases mixes typical of services designed for the chronically mentally ill are discussed.