The Medicare prospective payment system does not adequately account for severity of illness. Whether teaching hospitals treat a case mix of patients with more severe illness than do nonteaching hospitals was tested in a study using two severity measures, Horn's severity of illness index and Gonnnella's "disease staging." (Author/MLW)

Medicine needs a revised conceptual framework: biologic concepts need to be joined with concepts stemming from social, economic, governmental, and cultural phenomena. Health should be understood in sociocultural and behavioral as well as biological terms. (MLW)