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Government Funding Lapse

Because of a lapse in government funding, the information on this website may not be up to date, transactions submitted via the website may not be processed, and the agency may not be able to respond to inquiries until appropriations are enacted. The NIH Clinical Center (the research hospital of NIH) is open. For more details about its operating status, please visit  cc.nih.gov. Updates regarding government operating status and resumption of normal operations can be found at OPM.gov.

Diet History Questionnaire (DHQ) Datasets

The Diet History Questionnaire (DHQ) is a food frequency questionnaire that was added in 1998 and was administered to both arms of the trial. The questionnaire data has been processed so that the dataset contains nutrient data in grams. Many of the events in the trial occur prior to this questionnaire. To learn more about the Diet History Questionnaire (DHQ) data collected as part of the study, visit the PLCO Diet History (DHQ) documentation page.

For each dataset, a Data Dictionary that describes the data is publicly available. In order to obtain the actual data in SAS or CSV format, you must begin a data-only request. Data will be delivered once the project is approved and data transfer agreements are completed.


User Guides and Other Files

User Guides are intended to serve as a guide to using the data contained in these datasets.

For PLCO:
PLCO User Guide
(PDF - 291.4 KB)
For Diet History Questionnaire (DHQ) Data:
Data Dictionary
(PDF - 1.0 MB)
User Guide
(PDF - 368.5 KB)

Data-Collection Forms

The following forms were used to collect data that is now available in the datasets listed above. They are provided in PDF format.

Dietary History Questionnaire
DHQ - Scanned (6.1 MB)