A report by the Robert Wood Johnson Foundation (RWJF) examined an Iowa program under which parents are asked to indicate their dependent children’s health status on their tax forms to facilitate Children’s Health Insurance Program (CHIP) enrollment. 

From the report:

Despite rigorous outreach efforts by states, five million children who are eligible for Medicaid or the Children’s Health Insurance Program (CHIP) remain uninsured (Figure 1). This represents roughly 70 percent of all uninsured children in the U.S. (Dubay, Cook, & Garret, 2009) The passage of the Children’s Health Insurance Program Reauthorization Act (CHIPRA) underscores the importance of enrolling uninsured eligible children, as the 2008 legislation includes financial incentives for states to maximize enrollment in these programs. Specifically, future CHIP funding allocations from the federal government will be based on a state’s net enrollment change relative to current CHIP enrollment. Increased CHIP enrollment will bring about a larger allocation; lower enrollment will mean a reduced allocation. In addition, increased Medicaid enrollment can help states qualify for performance bonuses.

Full Report: Reaching Uninsured Children: Iowa’s Income Tax Return and CHIP Project (PDF | 365 KB) 

Robert Wood Johnson Foundation. (2010). Reaching uninsured children: Iowa's income tax return and CHIP project. FreshourJohnston, B.