Reduced incidence and mortality from colorectal cancer with flexible-sigmoidoscopy screening: A meta-analysis

Table 1 Characteristics of included studies on screening flexible sigmoidoscopy and colorectal cancer incidence and mortality

Ref.	Location	Study period (median follow-up time)	Age range (yr)	No. of patients per group	Study design	Total number of CRC cases	Incidence rate1(95%CI)	Number of deaths due to CRC	CRC Mortality rate1	Study quality
Atkin et al[18], 2010	United Kingdom	11.2 yr	55-64	(C): 113195	FS	(C): 1818	(C): 149 (143 -156)	(C): 538	(C): 52 (48-56)	7
				(S): 57237	Colonoscopy on detection of high risk polyps	(S): 706	(S): 114 (106-123)	(S): 189	(S): 36 (31-41)
Hoff et al[20], 2009	Norway	7 yr	55-64	(C): 41913	FS/FS + FIT	(C): 362	(C): 134	(C): 99		7
					Colonoscopy on detection of high risk polyps	(262 advanced CRC)
				(S): 13823		(S): 123	(S): 132	(S): 24
						(78 advanced CRC)
Schoen et al[17], 2012	United States	11.9 yr	55-74	(C): 77455	FS	(C): 1287	(C): 152 (144-160)	(C): 341	(C): 39 (35-43)	8
					Follow-up FS at 3-5 yr	(537 advanced CRC)
				(S): 77445	Colonoscopy on detection of any polyp	(S): 1012	(S): 119 (112-127)	(S): 252	(S): 29 (25-32)
						(381 advanced CRC)
Segnan et al[19], 2011	Italy	10.5 yr	55-64	(C): 17144	FS	(C): 306	(C): 176 (158-197)	(C): 83	(C): 44 (36-65)	7
					Colonoscopy for high risk Polyps	(152 advanced CRC)
				(S): 17148		(S): 251	(S): 144 (127-163)	(S): 65	(S): 35 (37 -55)
						(112 advanced CRC)

¹Rate per 100000 person years of follow-up. (C): Control group; (S): Screened group; CRC: Colorectal cancer; FS: Flexible sigmoidoscopy.