Table 1.

Definitions of screen-detected (SD) CRC and non–screen-detected CRC.

Nomenclature	Definition
SD-CRC	CRC diagnosed within the Flemish CRC screening programme after a positive FIT (≥15 µg/g), within six months after first subsequent colonoscopy and before next recommended FIT invitation (24 months)
Non–SD-CRC	FIT interval cancer (FIT IC): CRC diagnosed after a negative FIT (<15 µgHB/g) and before the next FIT invitation (24 months)
	Post-colonoscopy interval cancer within a FIT screening programme: CRC diagnosed after a positive FIT (≥15 µgHB/g), more than six months after first subsequent colonoscopy and before recommended follow-up (10 years)
	Colonoscopy non-responder CRC: CRC diagnosed in participants who are screened positive by FIT but do not adhere to colonoscopy follow-up, and diagnosis is determined by other means than colonoscopy within two years
	FIT non-participant CRC: CRC diagnosed in individuals from the screening target population who did not participate within 10 years after first FIT invitation

CRC: colorectal cancer; FIT: faecal immunochemical test.