Research Data Center (RDC)
A pathway to accessing SAMHSA's National Survey on Drug Use and Health (NSDUH) Restricted Use File
Substance Abuse and Mental Health Services Administration (SAMHSA) Restricted Use Data
The National Survey on Drug Use and Health (NSDUH) is a premier population health survey.
NSDUH measures:
- use of illegal drugs, prescription drugs, alcohol, tobacco, and misuse of prescription drugs
- substance use disorder and substance use treatment, major depressive episodes and depression care
- serious psychological distress, mental illness, and mental health care
NSDUH data provide estimates of substance use and mental illness at the national, state, and substate levels. NSDUH data also help identify the extent of substance use and mental illness among different subgroups, estimate trends over time, and determine the need for treatment services. NSDUH releases two versions of data yearly. The restricted use file (RUF) is not publicly accessible because it contains sensitive information such as zip code and other geographic identifiers. The public use file (PUF) is created from the RUF by applying disclosure control techniques and is publicly available online.
The research data center (RDC) program provides a mechanism for data users to access NSDUH restricted-use data files in a secure, confidentiality-compliant manner. SAMHSA RDC does not have it’s own RDC facilities. SAMHSA RDC collaborates with the National Center for Health Statistics (NCHS) RDC and the Federal Statistical Research Data Centers (FSRDC) to carry out the SAMHSA RDC program. All SAMHSA RDC users should carefully read "Guidelines for SAMHSA RDC Data Users" before accessing RUF data.
Please visit the section below for details:
- Latest Announcements
- Virtual Data Enclave (VDE)
- Confidential and public use data files
- Application process
- Application fee
- Security protocol
- Accessing files
- Output
- Resources for preparing the application
- Contact information
Latest Announcements
This section announces the latest NSDUH data changes that are (1) important for RDC data users to notice and (2) not yet covered by the relevant guidelines/documents at the time when the announcement is made.
- January 2024. An updated 2021 NSDUH RUF was released. This latest version contains an updated weight that allows for comparison of the 2021 NSDUH data to the 2022 NSDUH and subsequent years. To access the supplemental 2021 NSDUH codebook, see the “Resources” section below. For more information, please see the NSDUH 2021 Supplemental Codebook Summary.
Virtual Data Enclave (VDE)
The VDE is coming soon! The VDE will provide greater access to NSDUH data by allowing approved researchers to access the RUF without physically going to an RDC. With the VDE, researchers may designate a room at their host institution as the secure site as long as it meets all data security requirements. This could potentially save the data users time and money. The pilot implementation of the VDE began early 2023. SAMHSA RDC will inform researchers via our “Latest Announcements” section when the VDE will be fully operational.
Confidential and public use data files
NSDUH RUF is available from 2004 to the latest release of the most recent surveys. RUFs contain more data than the public use files, both in terms of the number of records and number of variables.
Comparison between the NSDUH public use and restricted use files (Note: There could be small variations between years.)
Confidential and Non-Public Use Variables
- Fully Specified Industry and Occupation Codes: These codes allow a worker's employment to be identified by industry and occupation (available through 2014).
- Region, State, and County FIPS Codes: These codes can be used to merge any data at the region, state, and/or county level onto the NSDUH data.
- Non-Public Use Data Elements: These are data elements from our questionnaires that are not directly identifiable data—sensitive in nature and not available in the public use files—such as age, detailed race-ethnicity, life experiences, and sexual identity (LGB).
Application process
General information
Prospective researchers must submit an RDC application, also known as an RDC proposal, that will be reviewed by the SAMHSA RDC team. The proposal must be approved before any other procedures can happen. The SAMHSA RDC review process ensures careful adherence to all requirements specified in "Guidelines for SAMHSA RDC Data Users" and "RDC sample proposal". In addition to the format and completeness, there are two aspects that are critical for the application to successfully pass SAMHSA review:
- The feasibility of existing data to the project, that is, whether it is possible for the research to be conducted with the available information. On occasion, it is clear from the outset that the sample will not support the intended analysis. For instance, NSDUH does not allow for individual-level record linkage.
- The risk of disclosure of restricted information, that is, whether the analysis can be conducted without compromising the confidentiality promised to all respondents (children, adults, households, neighborhoods).
If necessary, we may request additional revisions from the researchers or data users. If all requirements are met, the application will be approved. Approval of the proposal does not constitute endorsement by SAMHSA of the substantive, methodological, theoretical, policy relevance, or scientific aspects of the proposed research.
Conventional or non-SAP application
Since December 2022, SAMHSA, along with 15 other statistical agencies across the federal government, has utilized the Standard Application Process (SAP) portal for processing applications (see below). Non-SAP projects, which are RDC projects approved prior to the SAP implementation, should continue to use the conventional process to correspond with SAMHSA RDC. This would include submitting revisions and amendments, if any, to SAMHSA via email at RDCA@samhsa.hhs.gov.
Application via SAP portal
All federal statistical agencies, including SAMHSA, are required to use the SAP. The SAP Portal is a web-based data catalog and common application that will serve as a “front door” to apply for restricted data from any of the 16 principal federal statistical agencies and units.
SAP was created jointly by 16 federal statistical agencies and units to meet the requirements of the Foundations for Evidence-Based Policymaking Act of 2018. The SAP Portal website is www.ResearchDataGov.org.
SAP was implemented in a phased approach. On December 8, 2022, the SAP Portal began accepting applications to access confidential microdata. Beginning December 8, 2022, SAMHSA and the other principal federal statistical agencies and units began transitioning applications to the SAP Portal. The timeframe for transitioning applications to the SAP Portal is as follows:
- Beginning late 2022 — SAMHSA RDC began accepting applications via RDCA@samhsa.hhs.gov mailbox or through the SAP Portal common application.
- Late 2022 - February 1, 2023 — SAMHSA RDC accepted applications using the conventional application process or the SAP Portal common application.
- February 1, 2023 — All applications requesting access to SAMHSA RDC data should be submitted through the SAP Portal common application.
Keep in mind that output requests will NOT be affected by the SAP and should be requested directly through RDCA@samhsa.hhs.gov. Also, amendments and revisions of applications submitted prior to December 8, 2022 will continue to be sent via RDCA@samhsa.hhs.gov.
Additional notes
Whenever there is an official notice that the SAP system is not working properly, data users may create and submit applications using the conventional process (see above). Applications approved prior to the SAP implementation will continue to submit documentation (e.g., updated variable selection list, amendments, etc.) via RDCA@samhsa.hhs.gov. Keep in mind that the output submitting process will NOT be affected by the SAP.
Application fee
SAMHSA's data hosting partner, the NCHS RDC network, charges a user fee for using the RDC and the services. The amount of the fee varies by volume, usage, and requests for technical assistance. For more information, please see "RDC fees" below.
Security protocol
Maintaining confidentiality is the primary objective of the restricted use data program. After approval of the application, researchers must complete the confidentiality training and sign the required forms to document their commitment to following the RDC disclosure review policies and procedures.
All researchers involved in the project are required to complete confidentiality training and submit a signed Designated Agent Form (DAF) with a notary signature. As the confidentiality training was developed by NCHS, SAMHSA RDC asks that researchers not use the DAF and DAA (DUA) forms linked in the training but rather use the DAF and DAA forms linked below. By signing the DAF, researchers become designated agents to access CIPSEA protected data. In addition, any analysts entering the RDC must sign the DAA (Data Access Agreement) form. The training certificate, along with the signed DAA and DAF, must be submitted to be considered a complete package. For students wanting to access NSDUH RUF, both students and their advisors must also sign the SAMHSA RDC Student Data User Acknowledgement form.
Researchers wanting to use a FSRDC must also secure Special Sworn Status. This process includes an application, background check, and a fee. The process takes on average 3–4 months and is facilitated by the designated FSRDC after the proposal has been approved. Non-US citizens can only use restricted use data at a FSRDC.
Accessing the data files
Researchers must conduct their study within the designated RDC, either at one of the four NCHS RDC locations or at one of the 31 FSRDC located throughout the US. Remote access is not available at this time. Once the application has been approved and the requisite security protocol has been completed, please reach out to the designated RDC to schedule an in-person appointment.
The SAMHSA Restricted Use Data Program allows researchers to merge RUF with approved external data while working at the RDC. The user-supplied data may consist of proprietary data collected and owned by the user or public use data. Proprietary or restricted use data obtained apart from SAP portal should be accompanied with written approval for use. All external data must be sent to SAMHSA RDC for approval. If approved, SAMHSA RDC will upload the external data to the researchers' analytic folder.
Output
What output can be taken from the RDC?
- Only populated shell tables that exist within an approved application.
- All materials, including populated table shells, must undergo disclosure review by SAMHSA prior to release.
- Researchers may request the release of the programming code as part of the output package submitted for review.
What output cannot be taken from the RDC?
- Output that does not match shell tables or figures within the approved proposal.
- Any output that could potentially identify respondents or small geographic areas, either directly or inferentially.
- Any direct or inferential identifiers not revealed in the public use files.
- Sample case printouts or screenshots.
- Output that does not follow the disclosure rules as outlined in "Guidelines for SAMHSA RDC Data Users".
- Intermediate output. Intermediate output can be created and used onsite at the RDC, but cannot be included in the output package submitted for review.
Resources for preparing your application
Getting started
- FAQ
- RDC locations: (1) NCHS RDC; (2) Census Bureau FSRDC
- RDC fees
- RDC sample proposal
Application resources and guidelines
- Guidelines for SAMHSA RDC Data Users
- RDC Output Summary Report
- Example of Data Dictionary
- Example of Table/Figure Shells
- NSDUH reports
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- NSDUH Methodology
Completing confidentiality requirements
- Confidentiality training
- Designated Agent Form (DAF) [PDF, 163 KB]
- Data Access Agreement (DAA) [PDF, 15KB]
- SAMHSA RDC Student Data User Acknowledgement [PDF, 138KB]
- Application [PDF, 121KB]
Contact information
SAMHSA Restricted Use Data Program
Substance Abuse and Mental Health Services Administration
Center for Behavioral Health Statistics and Quality
5600 Fishers Lane
Rockville, MD 20857
Email: RDCA@samhsa.hhs.gov