Over the last twenty-five years, Professor Frank Porell's research has largely focused on the health services utilization patterns of aged Medicare beneficiaries in both community and institutional settings. Most of his research entails the analysis of large individual medical claims databases to address health policy issues, particularly those related to effects and geographic and other contextual factors on health services utilization, and consequences of various access barriers on health and functional status. Much of Professor Porell's earlier research addressed specific concerns of the Medicare program, such as Medicare HMO capitation rate risk adjustment refinements.