Utility of an overlapping panel design in the MEPS to assess the impact of survey redesign modifications on health care estimates

National estimates of healthcare measures for the overall population and specific subgroups are critical to policymakers and others concerned with access to medical care and the cost and sources of payment for that care. The Medical Expenditure Panel Survey (MEPS) is designed to provide annual national estimates of the health care use, medical expenditures, sources of payment and insurance coverage for the U.S. civilian non-institutionalized population. In 2007, the survey experienced two dominant survey design modifications: a new sample design attributable to the sample redesign of the National Health Interview Survey, and an upgrade to the CAPI platform for the survey instrument, moving from a DOS to a Windows-based environment. This study examines the impact of these survey design modifications on the resultant national healthcare estimates. The overlapping panel design of the MEPS and its longitudinal features are particularly well suited to assess the impact of survey redesign modifications on estimates. Since two independent nationally representative samples are pooled to produce calendar year estimates, one has the capacity to compare estimates based on the “original survey design” in contrast to those derived from the “survey redesign.” Particular attention is given to assessing the level of convergence in healthcare estimates based on the alternative designs as well as the alignment of model based analyses that discern which factors are associated with specific health care measures. The paper concludes with a discussion of strategies under consideration that may yield additional improvements in the accuracy for these critical policy relevant survey estimates.