A Tale of Two Cities? The Heterogeneous Impact of Medicaid Managed Care in Kentucky

Does managed care produce lower health care utilization and costs through better aligned financial incentives and alternative delivery methods (the “pure” HMO effect) or by attracting more healthy enrollees (enrollee selection)? The purpose of this paper is to shed new light on this fundamental question using a quasi-experimental approach that exploits the timing and county specific implementation of Medicaid managed care plans in two distinct sub-sets of Kentucky counties in the late 1990s. We find large differences in the relative success of each region in reducing utilization that are likely driven by important differences in plan design. Asthmatic children enrolled in the plan that was successful at reducing utilization did not appear to suffer adverse health outcomes as a result.