Young adult dependent coverage: were the state reforms effective?

Objective: To examine the robustness of findings regarding state-level adult dependent coverage expansions using detailed outcomes that specify coverage source.

Data Sources: This study uses the 2001-2009 files of the Current Population Survey's Annual Social and Economic Supplement, covering calendar years 2000-2008, and considers young adults ages 19 through 29.

Study Design: Difference-in-differences methods were used to estimate the effect of state-level dependent coverage expansions on finely detailed categories of coverage, and falsification tests were used to evaluate the models themselves.

Principal Findings: Certain published results on state-level parental coverage expansions are flawed, with reported increases driven by changes in spousal coverage. Other published results appear to be in fact driven by parental coverage, but they are not robust to alternative model adjustments.

Conclusions: This study shows evidence that one study's results on "dependent" coverage are in fact driven by changes in rates of spousal coverage. Results from a second study, though not robust to use of a more conventional DD model, would seem to apply most strongly to individuals at ages at which one would typically have lost parental coverage before reform, consistent with a "passive" effect rather than an "active" effect that enrolls previously uninsured youths.