Colorectal cancer screening 2000: the role of colonoscopy in average-risk individuals.

Colorectal cancer fulfills all of the criteria of a disease process that is suitable for a screening program. Several screening tests are effective in preventing mortality from colorectal cancer and are widely recommended. Despite the lack of direct comparisons, there is compelling indirect evidence that programs using colonoscopy as the primary tool are likely to be more effective than programs using fecal occult blood testing or flexible sigmoidoscopy as initial strategies. Colonoscopy-first programs are more expensive initially, but their cost effectiveness may prove to be comparable with the currently recommended programs in certain settings.