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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.

Supplemental Questionnaire (SQX) Datasets

The Supplemental Questionnaire (SQX) was added between 2006 and 2008 and administered to both arms of the trial. Data includes risk factors such as demographics, history of health, smoking, medications, physical activity and gender specific details. To learn more about the Supplemental Questionnaire (SQX) data collected as part of the study, visit the PLCO Supplemental (SQX) 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 Supplemental Questionnaire (SQX) Data:
Data Dictionary
(PDF - 375.9 KB)
User Guide
(PDF - 211.8 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.

Supplemental Questionnaire
SQX - Scanned (957.4 KB)