The USPSTF guidelines on colorectal cancer can be frustrating. They give an extensive literature review. And they cover 7 competing methods for screening. They don't list them in order, and they seem to waffle re: prioritizing or ranking the methods - fOBT, FIT, fDNA, sigmoid, ct colonoscopy, and endoscopic colonoscopy. Why?

Here's the reason: the task force reasons (and rightly so in my opinion) that the biggest variable is actually getting the test done. So, their point is this: Use of four methods are good:

colonoscopy, FIT, sigmoid/FIT(together), CT colonoscopy. FIT-DNA is also good, but not efficient ( read as too expensive). gFOBT ( or the old guaiac test) and sigmoid alone are both better than not screening. But the other listed methods are better.