Colonoscopy’s effectiveness in preventing colorectal cancer or mortality has never been tested in a randomized clinical trial. However, "the National Polyp Study, a randomized trial of different intervals of surveillance after polypectomy, estimated that 76% to 90% of cancers could be prevented by regular colono-scopic surveillance exams," the panel said. "A single case-control study suggests that colonoscopy is associated with a lower incidence of colon cancer and a lower mortality."
For more information on the report, go to http://www.preventiveservices.ahrq.gov.
