Comparing low-severity hospital admissions in IPA HMOs and indemnity-type programs

This study compares the proportion of low-severity hospital patients in independent practice association (IPA) HMOs and indemnity-type programs. The length of stay of such low-severity patients is also studied. Admissions of IPA patients under age 65 to ten hospitals are compared with admissions to the same hospital of patients covered by Blue Cross and Blue Shield plans or commercial insurance programs. Admissions to the adult medical service for the eight most frequently occurring DRGs with 5 percent or more patients in the low-severity category are included. A Logit model of the probability of low-severity admission controlling for age, sex, DRG, and hospital shows no significant IPA effect. However, a multiple regression model shows that the IPAs have significantly lower average length of stay for these low-severity patients.