Determinants of managed care penetration.

This paper examines factors associated with differences in managed care penetration across geographic areas. Two alternative measures of managed care penetration are considered: the percentage of revenue physicians received from managed care contracts and market survey data on enrollments in managed care plans. Results are similar for both types of measures. Our analysis suggests that demographics, labor market characteristics and supply side variables including the level of concentration in hospital markets, hospital occupancy rates and the practice organization patterns of physicians are all important determinants of managed care penetration.