The rate of children without health insurance has hit an all-time low of 6 percent, according to a new report from the Center for Children and Families. The drop is largely attributable to the Affordable Care Act (ACA) and to states’ efforts to increase enrollment. States that have opted to expand Medicaid to low-income adults saw the largest improvement in children’s coverage, even though most uninsured children were already eligible for health insurance under Medicaid or the Children’s Health Insurance Program (CHIP) prior to ACA. The report uses American Community Survey data from 2014, the first full year of ACA implementation.

All Medicaid expansion states saw a decline in uninsured children, with an average decrease nearly twice that of non-expansion states. Much of the increase in children’s enrollment, especially in Medicaid expansion states, is likely due to enrollment of children who were already eligible. This is often referred to as the “welcome mat” effect. Multiple factors drive this effect, including increased awareness of Medicaid and automatic enrollment of children when their parents apply. Rhode Island and Colorado, two of the states with the greatest declines, were participants in the Work Support Strategies initiative, a targeted effort to coordinate programs to maximize enrollment of eligible children and adults.

In addition to the welcome mat effect, states can explore using three targeted enrollment options. As outlined in May 2013 guidance and extended as part of the August 2015 guidance, states can request a waiver to use Supplemental Nutrition Assistance Program (SNAP) data to identify those who are likely eligible for Medicaid. States may also use the waiver to identify newly eligible parents of children enrolled in Medicaid. Six states (AR, CA, IL, NJ, OR, WV) have used these strategies to enroll a total of 726,584 people.

A newer option provided to states in August 2015 allows the use of SNAP data to identify a smaller group of people who are certainly eligible for Medicaid. States must submit a State Plan Amendment to employ this strategy, which can be used on an ongoing basis for Medicaid enrollments and renewal s.

States that have not expanded Medicaid for adults can still use a version of targeted enrollment known as “Express Lane Eligibility,” which automatically determines children eligible for health insurance based on SNAP receipt.

West Virginia’s data demonstrates the impact of targeted enrollment strategies.

In 2013, prior to ACA implementation, West Virginia had a relatively low rate of uninsured children at 5.3 percent. This makes their  post-ACA rate (3 percent in 2014) all the more remarkable.  As the rate of uninsured children declines, it’s typically more difficult to identify those who are eligible yet uninsured, and broad public awareness or outreach strategies become less effective.

West Virginia coupled its Medicaid expansion with the state waiver targeted enrollment option. The state used SNAP data to identify people likely eligible for Medicaid, as well as targeted parents of children already enrolled in Medicaid.

Because income eligibility limits are similar for Medicaid and SNAP, the SNAP strategy employed by West Virginia is an effective way for states to identify who is likely to be eligible for Medicaid, conduct outreach to those individuals, and receive their consent for enrollment. This strategy may be especially effective at identifying children who are not enrolled in Medicaid despite traditionally being eligible. Using SNAP and other targeted strategies, West Virginia successfully enrolled 70,574 people in Medicaid.  Among all states, West Virginia saw the largest percent decline in the number of uninsured children from 2013 to 2014 (43.7 percent).

More states should follow the lead of West Virginia and use existing data to identify those who are likely eligible for Medicaid but not enrolled in the program.