What is the recommended age and frequency for colorectal cancer screening in average-risk adults?

Colorectal cancer screening guidelines updated by ACS in 2018 and USPSTF in 2021 to lower age from 50 to 45 due to increased CRC incidence in younger adults. Screening options for average-risk adults age 45-75: (1) Colonoscopy every 10 years — gold standard; can identify and remove polyps in one procedure; requires prep and sedation; (2) Fecal Immunochemical Test (FIT) annually — non-invasive stool test for blood; requires colonoscopy if positive; (3) FIT-DNA (Cologuard) every 1-3 years — stool test detecting DNA markers and blood; requires colonoscopy if positive; (4) Sigmoidoscopy every 5 years — examines only lower colon; (5) CT Colonography (virtual colonoscopy) every 5 years — imaging study; requires colonoscopy if abnormal; (6) Sigmoidoscopy plus annual FIT. Choice depends on patient preference, ability to undergo prep/sedation, cost, insurance, family history. Higher-risk individuals (family history, inflammatory bowel disease, certain genetic syndromes) need earlier and more frequent screening. After 75: individualized decision; ACS suggests through age 85 may benefit. Patient education: prep is the worst part of colonoscopy for most; many adults avoid screening due to anxiety; nurses can normalize the procedure and address concerns. Stool-based tests offer alternatives for those who decline colonoscopy.