The Challenge of Studying the Effects of Managed Care as Managed Care Evolves

The Challenge of Studying the Effects of Managed Care as Managed Care Evolves Managed care today, for both Medicare beneficiaries and others, bears increasingly less resemblance to the managed care plans of the early 1990s (Lesser, Ginsburg, and Devers 2003).Utilization management strategies such as gatekeeping and preauthorization are on the decline.Many health maintenance organizations (HMOs) are starting to look more like preferred provider organizations (PPOs) because of reductions in selective contracting.And cost sharing is increasingly shifting to patients.With Medicare reform looming, accompanied by heated debates about a larger role for managed care and competition, there is a heightened need for data on the performance of managed care in its current form.But managed care's rapid evolution has made it a moving target, particularly challenging to study in a timely fashion.Researchers often lack up-to-date data, so that studies frequently draw conclusions that have considerably less relevance when they are published than they would have had were managed care a more stable element in the health insurance market.But getting the data to keep up with managed care is difficult to achieve.Thus, at a minimum, the data used should contain elements pertinent to the contemporary status of managed care.Whether data sources are old or new, to have findings that are useful to policymakers, researchers must interpret their findings in the context of the changes managed care has undergone.Several papers in this issue of Health Services Research touch on different aspects of managed care.What they have in common is research involving data that predate recent changes in managed care, yet each provides valuable lessons for managed care's latest evolution.Despite the controversy over increasingly incorporating managed care and competition in Medicare, there is a growing recognition that managed care--in any of a variety of incarnations--will coexist with fee-for-service (FFS) Medicare (Gold 2003).This coexistence has the potential for influencing delivery and cost of care for FFS patients, known as spillover effects.While there is no overall consistent pattern, studies over the past three decades have shown some benefits from managed care in the FFS sector, including reductions in hospital spending, increased rates of cancer screening, and