In April 2024 the US Government Accountability Office (GAO) released a report related to the Medicaid Program titled “COVID-19 Vaccination Data Access and Strategies Used to Improve Immunization Rates.” GAO studied a sample of six states to determine how and if their Medicaid Programs were able to leverage COVID vaccination data from their state Immunization Information Systems (IIS) during the pandemic. Four of the six states were able to access data (CA, GA, MA, MI) from the IIS; two states were not primarily due to policy or regulation preventing Medicaid Program access (CT, ID).
The report does a good job of quickly summarizing the use case for IIS information access; the needs of the Medicaid Program in each state; the method used in each state to identify Medicaid CAID recipients in the IIS and query for their data; problems experienced getting data within the context of national initiatives related to IIS data access, including problems that the IIS had getting reliable and accurate data from clinical care, patient matching issues, and data volume impacts; enabling infrastructure such as the CDC’s Immunization Gateway; and outreach efforts among the Medicaid population enabled by this data.
The states that were able to use IIS data certainly found that it contributed to their assessment of disparities in vaccination coverage among Medicaid recipients, though in the heat of the pandemic, it was hard to attribute the effectiveness of their interventions to any single source since usually, multiple activities were going on at the same time (many of these strategies were detailed in an appendix). The report contains some nice diagrams of just how the state Medicaid programs accessed IIS data. There were some valuable lessons learned that can guide future Medicaid-IIS data interoperability.