The priority is screening, not colonoscopy.
Woolf
Steven H
SH
Jones
Resa M
RM
Rothemich
Stephen F
SF
Krist
Alex
A
D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000517:prevention & control*; D006801:Humans; D008403:Mass Screening / Q000379:methods