Table 1.
Characteristics of included studies
| Studies | Country | Sample size (No) | Age range (years) | Enrollment period | Follow-up (years) | Relative risk (95% CI) | CRC mortality risk per 100 000 person years (95% CI) | ARR per 100 000 person years (95% CI) | Intervention | |
|---|---|---|---|---|---|---|---|---|---|---|
| Control | Intervention | |||||||||
| Segnan et al 201115 | Italy | 34 272 | 55-64 | 1995-99 | 11.4 | 0.78 (0.57 to 1.08) | 44 (36 to 55) | 35 (27 to 44) | 9.8 (−3 to 22) | Once only lifetime FS |
| Schoen et al 201214 | USA | 154 900 | 55-74 | 1993-2001 | 11.9 | 0.74 (0.63 to 0.88) | 39 (35 to 43) | 29 (25 to 32) | 10 (5 to 15) | FS at baseline, another screening 3 or 5 years later |
| Atkin et al 201012 | UK | 170 432 | 55-64 | 1994-99 | 11.2 | 0.69 (0.59 to 0.82) | 52 (48 to 56) | 36 (31 to 41) | 16 (10 to 22) | Once only lifetime FS |
| Holme et al 201413 | Norway | 100 210 | 50-64 | 1999-2001 | 11.2 | 0.73 (0.56 to 0.94) | 43* (39 to 47) | 31* (24 to 38) | 11.7 (3 to 20) | Once only lifetime FS or once only lifetime FS and FOBT |
CRC=colorectal cancer;ARR=absolute risk reduction; FS=flexible sigmoidoscopy; FOBT=fecal occult blood testing
*Mortality rates are age adjusted rates reported by authors. The 95% confidence intervals are calculated using unadjusted data reported in the original publication.