Table 1. Characteristics of the 8 studies on physical activity and digestive system cancer risk included in the meta-analysis
Authors, year | Gender | Region | Subjects | Cases | Relative Risk (95%CI) for high vs low PA | Relative Risk (95%CI) forhigh vs moderate PA | Relative Risk (95%CI) for moderate vs low PA | Low PA defined by | Moderate PA defined by | High PA defined by | Adjustment factors (excluding age ,sex) |
|---|---|---|---|---|---|---|---|---|---|---|---|
Cohort studies | |||||||||||
 Esmaeilzadeh et al. 2013 | Women | Iran | 2162 | 1081 | 0.77 (0.50, 1.19) | 0.96 (0.56, 1.56) | 0.80 (0.76, 0.83) | Low PA | Moderate PA | High PA | None |
 Lei et al. 2015 | Women | China | 367 | 310 | 0.38 (0.11, 1.29) | None | None | Non-exercise | None | ≥ 180 min/week | Adjusted on occupational exposure, family income, menstruation,Chinese herbal medicine use, alcohol consumption |
 Cong et al. 2016 | Women | China | 670000 | 5131 | 0.58 (0.42, 0.81) | 2.32 (1.25, 4.20) | 0.25 (0.10, 0.65) | Light exercise | Regular PA | Heavy exercise | Adjusted for age at marriage, marriage age limit, weight andheight |
 Gudmundsdottir et al. 2009 | Women | Norway | 7774 | 3887 | 0.60 (0.30, 1.2) | 1.67 (1.53, 1.67) | 0.90 (0.60, 1.50) | Low PA | Medium PA | High PA | Adjusted for smoking and marital status |
 Rich-Edwards et al. 2002 | Women | England | 26125 | 830 | 0.63 (0.44, 0.91) | None | None | < 30 min/week | None | ≥ 420 min/week | Adjusted for time spent in moderate activity, recency of oralcontraceptive use, intake of alcohol, and cigarette smoking |
 Läänelaid et al. 2021 | MenWomen | Estonia | 64 64 | 128 | 0.94 (0.66, 1.35) 0.43 (0.30, 0.62) | 1.37 (1.33, 1.41) 1.11 (1.08, 1.13) | 0.69 (0.49,0.96) 0.39 (0.27, 0.55) | Sedentary | Moderate PA | Vigorous PA | Adjusted for age and registered time. |
Case-control studies | |||||||||||
 Forman et al. 1994 | Men | England | 1587 | 794 | 0.54 (0.32, 0.90) | None | None | Non-exercise | None | ≥ 900 min/week | Adjusted for undescended testis and inguinal hernia diagnosed < 15 years |
 Green et al. 1986 | Women | American | 200 | 100 | 0.90 (0.20, 3.60) | None | None | Non-exercise | None | ≥ 150 min/week | Adjusted for race, census tract of residence, Reference year, parity, and times married. |
Foucaut et al. 2019 | MenWomen | French | 151151 | 7980 | 0.45 (0.22, 0.94) 0.63 (0.29, 1.37) | None | None | < 150 min/week | None | ≥ 150 min/week | Adjusted for educational level and for all variables of the table |
Dhair et al. 2020 | Women | Palestine | 320 | 160 | 0.32 (0.17, 0.63) | 0.75 (0.42, 1.35) | 0.43 (0.40, 0.46) | Low PA | Moderate PA | High PA | None |