The Centers for Medicare and Medicaid Services (CMS) have a contract with the Research Data Assistance Center (ResDAC) to facilitate data access requests. Their website (www.resdac.org) provides all the necessary information for development of requests for both restricted and limited datasets, and their staff can provide specific advice as you develop the request.
One of the requirements to get access to the Medicare data is a letter of support from your Program Officer. In order to do that, send an email to your Program Officer describing your request and how it relates to your funded grant. Please attach a copy of the cover letter you will send to the Centers for Medicare and Medicaid Services, the research summary, and, if it is a new request, a copy of the Data Use Agreement form for your Program Officer to sign.