Post Affordable Care Act Evaluation
Condition: Chronic Disease
MeSH terms: Chronic Disease
Study type: Observational

Summary: 
      This innovative study will measure the impact of Affordable Care Act-sponsored Medicaid
      expansions on access to and utilization of community health center (CHC) services. Building
      on the investigators prior work that developed a robust community-based research
      infrastructure within the OCHIN community health information network, the investigator will
      utilize linked electronic health record data from the OCHIN network of >400 CHC clinics in 8
      states that expanded Medicaid coverage and 8 states that did not expand.
    

Detailed description: 
      The Affordable Care Act (ACA) called for every state in the United States (US) to expand
      Medicaid coverage to individuals at ≤138% of the federal poverty level by 2014. In a 2012
      legal challenge, the Supreme Court ruled that states were not required to implement the
      ACA-sponsored Medicaid expansion; thus (by December 31, 2014), only 27 states and the
      District of Columbia expanded Medicaid, while 23 states did not. Little is known about the
      impact of ACA-sponsored Medicaid expansions on access to and changes in receipt of healthcare
      services among vulnerable populations. Yet this knowledge is essential to informing
      deliberations in 'non-expansion' states regarding whether to expand their Medicaid programs,
      and will also be helpful to 'expansion' states eager to learn about the impact of their
      expansions. The natural experiment created by the Supreme Court decision to make expansion
      optional for states provides a unique opportunity to assess the extent to which Medicaid
      expansions improve access to healthcare for low-income patients and other vulnerable
      populations. The proposed project will be one of the first to examine changes in access to
      and receipt of healthcare services and to Medicaid expenditures following ACA Medicaid
      expansions among a large population of safety net clinic patients. The investigators will use
      electronic health record data (EHR) from the OCHIN practice-based research network, which
      serves >1 million patients in 442 community health centers (CHCs) in 8 expansion states and 8
      non-expansion states. Moreover, using CHC data from the 8 expansion-states, the investigators
      will examine differences in utilization among patients gaining new Medicaid coverage (newly
      insured), as compared to those already insured by Medicaid (already insured), and those who
      remain uninsured (uninsured). Finally, the investigators will link EHR data from the 213
      OCHIN clinics in Oregon to Medicaid administrative claims data to assess overall healthcare
      utilization (including care received outside of CHCs, such as hospitalization) and to compare
      Medicaid expenditures among newly insured individuals versus those already insured. The
      investigators will address the following specific aims: Aim 1: compare pre-post health
      insurance status, primary care, mental health, and dental visits, and receipt of preventive
      services, as well as changes in payer mix among OCHIN CHCs in states that did and did not
      expand Medicaid; Aim 2: Examine pre-post utilization of CHC services (including receipt of
      preventive services) by newly insured patients compared to already insured patients and
      uninsured patients; and, Aim 3: Measure pre-post Medicaid expansion changes in overall
      utilization of healthcare services and costs to the Oregon Medicaid program among newly
      insured compared to already insured. The findings from this project will be extremely
      relevant to policy and practice, informing further improvements in the US healthcare system
      to ensure access to healthcare for vulnerable populations.
    

Intervention name(s): Medicaid Expansion
Intervention type(s): Other
Intervention description(s): There will be no direct intervention, but rather an observation of change based on whether a state expanded Medicaid or not
Observational model: Case-Control
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Study eligible patients within electronic health record data from the OCHIN community
        health information network
      
Keywords: healthcare access; utilization; expenditures; preventive services