Medicaid Acronym of the Day – MSIS

Medicaid Statistical Information System – The 25 MSIS statistical tables contain national state-by-state data. These tables contain high-level aggregated statistics relating to Medicaid eligibility and claims data.

Further reading 

https://www.cms.gov/Research-Statistics-Data-and-Systems/Computer-Data-and-Systems/MedicaidDataSourcesGenInfo/index.html