1. The Medicaid buy-in and Social Security Disability Insurance (DI) beneficiaries: lessons for the 2014 Medicaid expansion and proposals to reform DI Author(s): McInerney, Melissa, authorCenter for Retirement Research at Boston College, author. Publication: Chestnut Hill, MA : Center for Retirement Research at Boston College, December 2013 Subject(s): Disabled PersonsHealth Care ReformInsurance, DisabilityMedicaidSocial SecurityEligibility DeterminationEmploymentIncomeState GovernmentHumansUnited StatesUnited States.