Reporting on continuity of coverage for children in Medicaid and CHIP: what states can learn from monitoring continuity and duration of coverage.

Objective: The Children's Health Insurance Program Reauthorization Act (CHIPRA) requires states to measure and report on coverage stability in Medicaid and the Children's Health Insurance Program (CHIP). States generally have not done this in the past. This study proposes strategies for both measuring stability and targeting policies to improve retention of Medicaid coverage, using Ohio as an example.

Methods: A cohort of newly enrolled children was constructed for the 1-year time period between July 2007 and June 2008 and followed for 18 months. Hazard ratios were estimated after 18 months to predict the likelihood of maintaining continuous enrollment in Medicaid, adjusting for income eligibility group, age, race, gender, county type, and change in unemployment. Children dropping from the program at the renewal period (12-16 months) were followed for 12 months to determine their rate of return.

Results: Approximately 26% of children aged <1 year and 35% of children aged 1 to 16 years dropped from Medicaid by 18 months, with the steepest drop occurring after 12 months, the point of renewal. Likelihood of dropping was associated with the higher income eligibility groups, older children, and Hispanic ethnicity. Approximately 40% of children who were dropped at renewal re-enrolled within 12 months. Children in the lowest income group returned sooner and in higher proportions than other children.

Conclusions: A substantial number of children lose Medicaid coverage only to re-enroll within a short time. Income eligibility group appears to be a strong indicator of stability. Effective monitoring of coverage stability is important for developing policies to increase retention of eligible children.