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Colorectal

Among 22,000 follow-up endoscopies, data was collected on at least 30,000 polyps and 15,000 adenomas seen on endoscopy. Polyp counts, sizes, locations and histologies are included in the data when available.

For most purposes, adenoma and polyp data can be obtained within the Colorectal dataset. Additional details can be found in the Colorectal Endoscopies dataset (one record per endoscopy per person) and the Colorectal Polyps dataset (one record per polyp per endoscopy per person).

Summary Available Data
  • ~85,000 procedures among ~21,000 participants
  • Collected for the year following a positive screen or the year preceding a colorectal cancer diagnosis
  • Collected in the intervention arm for participants with colorectal cancer or screens suspicious for colorectal cancer. (~72,000 procedures among ~20,000 participants)
  • Collected in the control arm only for participants with colorectal cancer. (~13,000 procedures among ~1500 participants)
  • Collected on DEC (Diagnostic Evaluation - Colorectum) forms:
  • Whether screens prompted diagnostic procedure(s)
  • Whether screens prompted endoscopy
  • Type of endoscopy
  • Whether adenoma seen on endoscopy
  • Adenoma location (i.e., distal or proximal)
  • Available in diagnostic procedures, endoscopy and polyp datasets:
    • Types of procedures
    • Days from randomization to procedure
    • Bowel preparation for endoscopy
    • Cecum visualization at endoscopy
    • Adenoma location (e.g., sigmoid)
    • Whether adenoma is advanced
    • Whether adenoma is villous
    • Form version used to capture information

*77,000 participants were randomized for screening, but 10,000 never completed screening.