The World Mental Health Composite International Diagnostic Interview
The World Mental Health Survey Initiative
World Health Organization Health and Work Performance Questionaire
NCS and NCSR Data

1. Public Release of the NCS-R Dataset
The public use version of the NCS-R dataset is now available. The NCS-R dataset can be found at:

2. Public Release of the NCS-A Dataset
The public use version of the NCS-A dataset is now available. The NCS-A dataset can be found at:

3. NCS-R/NCS-A FAQ and Help Line
In an effort to help support public users, the NCS-R/NCS-A staff has established a FAQ section on their web site ( ICPSR has a subscriber help line that should always be consulted first, but questions that cannot be handled by the ICPSR help line will be referred to the NCS-R email support system. The latter will be directed to NCS-R/NCS-A data analysis staff, who will respond via email.

4. Am I required to go through CIDI training to obtain a copy of the dataset?
It is important to note that CIDI 3.0 training is not required to obtain a copy of the public use NCS-R/NCS-A datasets. However, the NCS-R/NCS-A FAQ and help desk will not entertain questions that deal with the CIDI (e.g., explanation of diagnostic algorithms), only questions specific to the NCS-R/NCS-A datasets, based on the fact that CIDI training is available separately, and the data analysts who support the NCS-R/NCS-A help desk are not experts in the CIDI. It is worth noting, though, that all the NCS-R/NCS-A analysts have themselves gone through CIDI training based on our belief that it is of great importance for analysts to understand the details of the data collection process in order to appreciate the complexities in the data they are analyzing. We strongly encourage public users to take the CIDI training course if they intend to work in depth with the NCS-R/NCS-A data.

While it is possible to carry out analyses of the NCS-R data without CIDI training, it is the experience of the NCS-R/NCS-A staff that the majority of questions of public users of the baseline NCS dealt with issues that are covered in CIDI training. It is important for us to emphasize that questions of this sort will no longer be answered by NCS-R/NCS-A staff in light of the fact that CIDI training is now readily available.

For information about CIDI training please click here.


All NCS datafiles, codebooks, and the questionnaire for the original 1990-1992 survey are currently public access and are archived by SAMHDA at the Inter-university Consortium for Political and Social Research (ICPSR). All files can be downloaded from the links on the SAMHDA web site:

Instructions for downloading files can be found on the web site. Technical support for accessing the data can be obtained by contacting the SAMHDA staff directly.

The files you will find at are:

DS1: NCS Main Data

Data (31372K); Questionnaire PDF (1289K); SAS data definition statements (1845K); SPSS data definition statements (1677K)

DS2: NCS Diagnosis/Demographic Data*

Codebook PDF (520K); Data (2547K); SAS data definition statements (82K); SPSS data definition statements (77K)

DS3: Codebook for NCS Main Data, Volume 1

Codebook PDF (1978K)

DS4: Codebook for NCS Main Data, Volume 2

Codebook PDF (1805K)

*Note for diagnostic codebook:
GAD1M1 is GAD 30 day without hierarchy and GAD1M2 is GAD 30 day with hierarchy. GAD6M1 is GAD 6Month without hierarchy and GAD6M2 is GAD 6Month with hierarchy.

*Click here for NCS-R training materials.