Integrating the health services and insurance industries (HMOs) could lower expenditure by reducing either the quantity of services or unit price. We compare the treatment of heart attacks and newly diagnosed chest pain in HMOs and traditional plans in two data sets. The nature of these health...

Managed care may affect medical treatments for non-managed-care patients if it alters local market structure or physician behavior. We investigate whether higher levels of overall managed care market share are associated with greater use of recommended therapies for fee-for-service patients with...