The Center for Health Care Strategies (CHCS) released a brief examining methods of linking Medicare and Medicaid data.  The brief offers information on the types of Medicare data available to states, how to access it, and how it can be used in concert with states' Medicaid programs.  The authors note that the data can be challenging to access and properly utilize, but suggest that if used correctly it can both improve care and reduce costs.

From the report: While Medicare and Medicaid generally cover different populations, there are nearly nine million people eligible for both programs. These “dual eligible” beneficiaries represent the most chronically ill and costly segments of both the Medicare and Medicaid populations. Integrating Medicare and Medicaid offers tremendous potential to both improve care and control costs.

Full report: Integrating Medicare and Medicaid Data to Support Improved Care for Dual Eligibles (PDF | 134 KB)   

Center for Health Care Strategies.  (2010).  Integrating Medicare and Medicaid data to support improved care for dual eligibles.