“…Similarly, among low-income insured residents, we observe geographic variation in the percentages of individuals covered by programs such as Medicaid, and the State Children's Health Insurance Program (SCHIP). The eligibility criteria for these public programs vary by state and depend on the availability of federal and state funds to pay for medical care for low-income people (Norton and Lipson 1998;Brown, Wyn, and Teleki 2000;Bindman et al 2000;Lillie-Blanton and Lyons 1998;Bronstein and Adams 1999;Adams and Bronstein 1999). Because of the categorical and episodic nature of Medicaid eligibility and changes in state regulations and financing, individuals cycle on and off insurance, often with long spells of no insurance Short, Graefe, and Schoen 2003;IOM 2000;Kasper, Giovannini, and Hoffman 2000;Schoen and DesRoches 2000;Brown et al 1999;Short 1998;Davis 1996;Short and Lefkowitz 1992;Short, Cornelius, and Goldstone 1990;Short, Cantor, and Monheit 1988).…”