Table 1.

Grouping of Treatment and Control States for Medicaid Expansion

Excluded States
Alaska1 Montana1 Indiana1 Arizona2,4 North Dakota3,4
Control States
Alabama Delaware Florida Georgia Idaho Kansas Maine Massachusetts Mississippi Missouri Nebraska New York		North Carolina Oklahoma South Carolina South Dakota Tennessee Texas Utah Vermont Virginia Washington, DC Wisconsin4 Wyoming
Treatment States
Extensive Dental Coverage	Limited Dental Coverage		Emergency Dental Coverage
California Connecticut Iowa New Jersey New Mexico Ohio Oregon Rhode Island Washington	Arkansas Colorado Illinois Indiana Kentucky Michigan Minnesota Pennsylvania		Hawaii Maryland Nevada New Hampshire West Virginia

Notes:

¹indicates states that were excluded in the main estimation of the difference-in-differences model identifying the Medicaid expansion effects because these states expanded in later 2015 and 2016.

²Arizona was excluded in the main estimation because it is a Medicaid expanding states but offers no dental coverage.

³North Dakota was excluded in the main estimation because it expanded Medicaid in 2014 and provides extensive dental coverage for traditional Medicaid adults, but not for expansion adults.

⁴In a sensitivity analyses, Wisconsin was switched from a control state to treatment state. Arizona and North Dakota were added as control states.