Risk factor	Age to initiate screening	Interval if normal (years)
Single first-degree relative with colorectal cancer or an advanced adenoma diagnosed at ≥ 60 years of age	50 years (may start at 45 years in blacks)	10
Single first-degree relative with colorectal cancer or an advanced adenoma diagnosed at < 60 years of age	40 years or 10 years younger than affected relative's age when diagnosed, whichever is earlier	5
Two first-degree relatives with colorectal cancer or an advanced adenoma diagnosed at any age	40 years or 10 years younger than the youngest affected relative's age when diagnosed, whichever is earlier	5