Comparing hospital length of stay in independent practice association HMOs and traditional insurance programs.

This study compares length of hospital stay in Independent Practice Association (IPA) HMOs and traditional insurance programs. Hospital admissions from 10 IPAs are compared with admissions to the same hospital of persons covered by Blue Cross and Blue Shield Plans or commercial insurance programs. Admissions of patients under age 65 to the adult medical service for the 10 most frequently occurring DRGs are included. Regression equations are estimated using length of stay as the dependent variable and IPA membership and hospital and patient characteristics as control variables. All 10 IPAs exhibit shorter lengths of stay as indicated by negative beta coefficients, and in 6 of the 10 IPAs this coefficient is statistically significant (p less than .05). This IPA effect occurs for 7 of the 10 study DRGs, and for MedisGroups Admission Severity Groups 0, 1, and 2.