Medical Statistical Information System (MSIS)

Data Set: Medical Statistical Information System (MSIS)

Collected By: CMS

Sample Coverage and Dataset Characteristics: Since the Balanced Budget Act (BBA) of 1997, all claims submitted to CMS are processed electronically through MSIS.  MSIS data are used by CMS to produce Medicaid program characteristics and utilization information for states.  These data also provide CMS with a large-scale database of state eligibles and services.  The purpose of MSIS is to collect, manage, analyze, and disseminate information on eligibles, beneficiaries, utilization, and payment for services covered by State Medicaid programs.

Key Variables: Each state eligible file contains one record for each person covered by Medicaid for at least one day during the reporting quarter.  Individual eligible records consist of demographic and monthly enrollment data.  Paid claims files contain information from adjudicated medical service related claims and capitation payments.  Four types of claims files representing inpatient, long-term care, prescription drugs, and noninstitutional services are submitted by the states.  Claims records contain information on the types of services provided, providers of services, service dates, costs, types of reimbursement, and epidemiological variables.

Documentation: http://www.cms.hhs.gov/msis/

Indicative Studies/Presentations:

• Zerzan, J. T., Morden, N., Soumerai, S., et. al. (2006). Trends and Geographic Variation of Opiate Medication Use in State Medicaid Fee-For-Service Programs, 1996 to 2002. Medical Care, 44(11), 1005-1010.
• Holahan, J. & Ghosh, A. (2005). Understanding The Recent Growth In Medicaid Spending, 2000-2003. Health Affairs Web Exclusive, January 26, 2005