Skip to Main Content

An official website of the United States government

The following PLCO Colorectal dataset(s) are available for delivery on CDAS. 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.

To learn more about the Colorectal data collected as part of the study, visit the PLCO Data Collected documentation page.

Datasets and Data Dictionaries

Files Description
Data Dictionary
(PDF - 460.8 KB)
1. The Colorectal dataset is a comprehensive dataset that contains nearly all the PLCO study data available for colorectal cancer screening, incidence, and mortality analyses. This dataset contains one record for each of the approximately 155,000 participants in the PLCO trial.
Data Dictionary
(PDF - 107.9 KB)
2. The Colorectal Screening dataset (~107,000, one record per year of screening) contains additional information from Flexible Sigmoidoscopy (FSG) cancer screens. This includes information like QA FSG exam results, reason for inadequate exam and additional findings that were not suspicious for cancer.
Data Dictionary
(PDF - 47.2 KB)
3. The Colorectal Screening Abnormalities dataset (~45,000, one record per abnormality) contains information for each lesion found during the FSG screen exam. This includes lesion type, location, and size.
Data Dictionary
(PDF - 72.6 KB)
4. The Colorectal Diagnostic Procedures dataset (~84,000, one record per procedure) contains information about the diagnostic procedures prompted by positive colorectal cancer screen, as well as diagnostic/staging procedures associated with any colorectal cancers diagnosed during the 13 years of follow-up.
Data Dictionary
(PDF - 54.0 KB)
5. The Colorectal Medical Complications dataset (~1,500, one record per medical complication) contains information about the medical complications caused by diagnostic workup for colorectal cancer.
Data Dictionary
(PDF - 46.0 KB)
6. The Colorectal Treatments dataset (~5,600, one record per treatment procedure) contains specifics of the initial treatment following the diagnosis of colorectal cancer.
Data Dictionary
(PDF - 123.4 KB)
7. The Colorectal Endoscopies (~22,000, one record per endoscopy) contains specifics of the endoscopies.
Data Dictionary
(PDF - 79.1 KB)
8. The Colorectal Polyps dataset (~27,000, one record per polyp) contains data about the individual polyps that were found during the follow-up to an FSG that was suspicious for colorectal cancer and polyps found during the diagnostic workup associated with the diagnosis of all colorectal cancers diagnosed during the trial. The information in this dataset includes the polyp's location, size and histology.

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)

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.

Baseline Questionnaire - Female
BQF3 - Scanned (1.7 MB)
Baseline Questionnaire - Male
BQM3 - Scanned (1.6 MB)
Flexible Sigmoidoscopy Screening Exam Form
FSG2 - Scanned (584.8 KB)
Colorectal Diagnostic Evaluation Form
DEC3 - Scanned (3.1 MB)
Colorectal Treatment Information Form
TIC2 - Scanned (1014.8 KB)
Annual Study Update Form
ASU - Scanned (82.2 KB)