Measurement of case mix

Describing hospitals quantitatively in terms of the numbers and types of patients treated (i.e., the patient case mix) offers the prospect of improved multihospital and longitudinal comparisons. Theoretically, an adequate measure of patient case mix could be used to: separate expense increases into changes in type of patients treated versus changes in practice patterns for an unchanged mix of patients; individualize third party payment limits to account for differences between a given hospital and the group with which it is being compared; justify or evaluate capital expenditure programs in terms of patient treatment patterns and resulting operating costs, and evaluate apparently atypical average lengths of patient stays and ancillary service patterns in utilization review programs. To date, these theoretical prospects have not been widely realized. However, recent developments in the measurement of patient case mix have lead to increased experimentation with available measures, and have stimulated interest and activity in developing new ones.