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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.

PLCO User Guide
(PDF - 394.1 KB)
For Supplemental Questionnaire (SQX) Data:
Data Dictionary
(PDF - 388.2 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)