t he growth of managed care as a mechanism to lower healthcare costs has led concerns that this may adversely affect quality relative reductions in payment the because hospitals have fewer resources with which provide services overall effect on patient declines reimbursement by particular insurer com prises 2 phenomena direct patients insurance who receive beneficial and an indirect or spillover other within same hospi tal whose is altered hospital wide resource constraints comparisons between health maintenance organization hmo fee for service ffs produced mixed results 1 3 however commercial penetration been shown effects cost among medicare observed areas high 4 5 addition er preferred provider rates be associated reduced access less use ly diagnostic testing 6
