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Access to Restricted Data

Restricted data is defined as data that cannot be released directly to the public research community due to possible risk(s) to study participants as well as the confidentiality promised to them. Gaining access to these datasets may be time consuming and researchers who wish to use these files are encouraged to explore the feasibility of gaining access before submitting an application for funding. Necessary funds for data purchase or data security plans should be included in the grant’s budget.

Grantees will need to develop their own requests for data use. The Inter-University Consortium for Political and Social Research may be able to assist you in finding datasets and gaining access. For Centers for Medicare and Medicaid Services (CMS) data use, researchers are urged to visit the Research Data Access Center (ResDAC). CMS now offers a new and secure way to access its data program through virtual access. The CMS Virtual Research Data Center (VRDC) is a virtual research environment that provides access to Medicare and Medicaid program data efficiently and effectively through a CMS-secured environment. Further, researchers can download cumulative reports and results to private computers. On ResDAC’s site is information for user requirements as well as how to request materials and submit information. As an NIA grantee, you will have to pay for CMS data. You will need to include estimated data costs for the purchase of these data in your grant application. The NIA does not pay for the data directly.

The NIA supports several data infrastructure projects that contain restricted data including the: HRS, Panel Income Dynamics Study (PSID), National Social Life, Health, and Aging (NSHAP) Project, Midlife in the United States (MIDUS) Study, and National Health and Aging Trends Study (NHATS). These studies, and many others, can facilitate limited access to these data for grantees. For more information, please contact Prisca N. Fall.

Access to Medicare Data

The Centers for Medicare and Medicaid Services (CMS) has a contract with the Research Data Assistance Center (ResDAC) to facilitate data access requests. The ResDAC website ( provides all of the necessary information on how to obtain Medicare and/or Medicaid data for researchers, including requests for both restricted and limited datasets as well as public use files (PUF)/non-identifiable files. CMS data are used to complete the specific aims of an NIA grant.

The first step in obtaining CMS data involves submitting a new request to ResDAC for Research Identifiable Files (RIF) and a RIF Data Use Agreement (DUA). An overview of the timeline and process for requesting RIF data is presented in ResDAC’s Knowledgebase article. A ResDAC Technical Advisor will review your request for accuracy and completeness; the ResDAC Advisor is there to ensure your application for data is as strong as possible before it is submitted to CMS. To review the materials needed for your request, see ResDAC’s RIF Data Request page. If you have more questions, ResDAC staff can provide specific advice as you develop your request(s).

In order to obtain access to Medicare data for new research projects, you will need to provide a copy of your RIF DUA form for your Federal Program Officer (FPO) to sign. A DUA is an agreement for use of CMS data containing individual identifiers. The form outlines in detail the confidentiality requirements of the Privacy Act and CMS' data release policies and procedures. For researchers who already have an existing DUA, but are requesting additional data years and/or files, you must complete a DUA Update form. This document is not signed nor finalized until the end of the ResDAC review process.

Once you have an established DUA, you may request a Letter of Support (LOS) from your FPO and make amendments1 as updated data files become available. In order to do that, send an email to your FPO citing your active NIA grant number, grant title, your request, and how it relates to your funded grant. Templates of NIA-approved LOS’ are available and accessible on ResDAC’s website.

1An amendment request to a DUA includes adding new years of data files covered previously under the DUA, adding new data files not covered under the DUA, making a change to the CMS-approved data management plan, and adding new study personnel to the DUA. Each of these amendment request types requires different documentation and necessary steps for CMS review and approval. For specifics on documentation and necessary steps, refer to the additional information provided on the ResDAC website. Please note that changing the specific aims on a research protocol at the inactive stage of an NIA grant will not acquire NIA support.

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