Accuracy
Some screening methods are better at finding polyps and cancer than others. Here's how each test rates on a scale of one (least accurate) to 5 (most accurate) stars.
Colonoscopy
- Has highest accuracy rate.
- Finds cancers and large polyps in 9 out of 10 patients who have cancers or large polyps.
- Finds most small polyps.
Virtual Colonoscopy
- Has second-highest accuracy rate.
- Finds cancers and large polyps in nearly 9 out of 10 patients who have cancers or large polyps.
- Misses many small polyps.
Flexible Sigmoidoscopy
- Has medium accuracy rate.
- Finds cancers and large polyps in 7 out of 10 patients who have cancers or large polyps.
- Only examines the lower third of the colon.
Barium Enema
- Has medium accuracy rate.
- Finds cancers in 8 out of 10 patients who have cancers.
- Misses many large polyps.
FOBT
- Has lowest overall accuracy rate.
- Finds most cancers, but misses most large polyps.
- The test may be positive in up to 1 in 10 patients who do NOT have cancers or large polyps (false positive).
Stool DNA Test
- Old test (PreGen-Plus) test found most cancers but missed most large polyps.
- New test (Cologuard) test has a high accuracy for finding both cancers and large polyps.
No Test
- No chance of finding polyps or cancer.