Table 2. Comparison of pooled relative risks in cohort and case–control studies.
| Cancer site | Alcohol intake | N | Cohort Pooled RR (95% CI) | I2 | N | Case–control Pooled RR (95% CI) | I2 | Pa |
|---|---|---|---|---|---|---|---|---|
| Oral cavity and pharynx | Light | 4 | 0.86 (0.60–1.23) | 68 | 22 | 1.22 (1.10–1.35) | 0 | 0.007 |
| Moderate | 5 | 1.25 (1.02–1.53) | 16 | 47 | 1.91 (1.69–2.16) | 70 | ||
| Heavy | 3 | 3.13 (1.59–6.19) | 69 | 35 | 5.34 (4.46–6.39) | 77 | ||
| Oesophageal SCC | Light | 10 | 1.20 (0.84–1.71) | 84 | 24 | 1.29 (1.07–1.55) | 49 | 0.157 |
| Moderate | 13 | 1.92 (1.44–2.58) | 83 | 40 | 2.34 (1.87–2.92) | 86 | ||
| Heavy | 9 | 3.56 (2.25–5.64) | 91 | 32 | 5.43 (4.04–7.32) | 91 | ||
| Oesophageal AC and gastric cardia | Light | 4 | 0.88 (0.74–1.03) | 6 | 17 | 0.88 (0.74–1.04) | 38 | 0.474 |
| Moderate | 4 | 0.82 (0.62–1.07) | 50 | 17 | 1.06 (0.78–1.43) | 75 | ||
| Heavy | 1 | 1.11 (0.48–2.56) | 0 | 17 | 1.16 (0.95–1.41) | 40 | ||
| Stomach | Light | 19 | 0.94 (0.87–1.03) | 55 | 16 | 1.08 (0.93–1.26) | 57 | 0.227 |
| Moderate | 19 | 0.96 (0.88–1.06) | 62 | 20 | 0.98 (0.89–1.08) | 11 | ||
| Heavy | 9 | 1.15 (1.03–1.28) | 0 | 11 | 1.22 (0.97–1.54) | 65 | ||
| Colorectum | Light | 33 | 1.01 (0.95–1.06) | 22 | 32 | 0.97 (0.89–1.06) | 53 | 0.129 |
| Moderate | 33 | 1.20 (1.12–1.29) | 45 | 33 | 1.14 (1.05–1.25) | 58 | ||
| Heavy | 14 | 1.41 (1.23–1.63) | 46 | 15 | 1.46 (1.15–1.86) | 78 | ||
| Liver | Light | 9 | 0.85 (0.74–0.97) | 32 | 12 | 1.31 (0.97–1.78) | 23 | 0.226 |
| Moderate | 9 | 1.00 (0.87–1.17) | 58 | 27 | 1.15 (0.97–1.35) | 40 | ||
| Heavy | 7 | 1.12 (1.02–1.23) | 0 | 24 | 2.79 (2.00–3.87) | 76 | ||
| Pancreas | Light | 18 | 0.95 (0.89–1.01) | 40 | 18 | 0.97 (0.84–1.13) | 42 | 0.363 |
| Moderate | 18 | 1.06 (0.99–1.13) | 28 | 21 | 0.97 (0.88–1.06) | 8 | ||
| Heavy | 9 | 1.18 (1.08–1.28) | 0 | 13 | 1.16 (0.98–1.37) | 17 | ||
| Larynx | Light | 3 | 0.81 (0.61–1.07) | 21 | 11 | 0.88 (0.61–1.27) | 45 | 0.216 |
| Moderate | 3 | 1.09 (0.70–1.72) | 46 | 34 | 1.48 (1.28–1.73) | 62 | ||
| Heavy | 3 | 1.12 (0.75–1.67) | 0 | 33 | 2.81 (2.33–3.39) | 76 | ||
| Lung | Light | 18 | 0.85 (0.82–0.89) | 26 | 11 | 0.71 (0.57–0.89) | 57 | 0.882 |
| Moderate | 18 | 0.97 (0.91–1.04) | 60 | 14 | 1.03 (0.87–1.21) | 51 | ||
| Heavy | 13 | 1.07 (0.93–1.25) | 75 | 7 | 1.33 (1.07–1.66) | 51 | ||
| Malignant melanoma | Light | 2 | 1.25 (1.13–1.38) | 0 | 12 | 1.06 (0.90–1.25) | 32 | 0.156 |
| Moderate | 2 | 1.27 (1.13–1.42) | 0 | 10 | 1.16 (0.92–1.45) | 47 | ||
| Heavy | – | n.e. | n.e. | – | n.e. | n.e. | ||
| Breast (female) | Light | 42 | 1.06 (1.03–1.10) | 41 | 73 | 1.04 (0.99–1.09) | 69 | 0.745 |
| Moderate | 37 | 1.22 (1.17–1.27) | 31 | 58 | 1.23 (1.16–1.32) | 62 | ||
| Heavy | 6 | 1.50 (1.19–1.89) | 0 | 5 | 1.78 (1.27–2.50) | 28 | ||
| Endometrium | Light | 8 | 0.97 (0.92–1.02) | 4 | 13 | 0.95 (0.87–1.03) | 14 | 0.631 |
| Moderate | 5 | 1.06 (0.89–1.26) | 67 | 8 | 0.87 (0.64–1.18) | 78 | ||
| Heavy | – | n.e. | n.e. | – | n.e. | n.e. | ||
| Ovary | Light | 4 | 1.02 (0.96–1.08) | 0 | 16 | 0.94 (0.87–1.01) | 17 | 0.007 |
| Moderate | 4 | 1.08 (0.99–1.19) | 20 | 13 | 0.99 (0.88–1.12) | 43 | ||
| Heavy | – | n.e. | n.e. | – | n.e. | n.e. | ||
| Prostate | Light | 19 | 1.04 (1.01–1.08) | 0 | 17 | 1.04 (0.97–1.11) | 0 | 0.773 |
| Moderate | 20 | 1.06 (0.99–1.13) | 24 | 21 | 1.06 (0.99–1.14) | 15 | ||
| Heavy | 8 | 1.04 (0.90–1.21) | 45 | 10 | 1.12 (0.95–1.33) | 37 | ||
| Bladder | Light | 3 | 1.10 (0.87–1.41) | 49 | 16 | 0.96 (0.85–1.09) | 37 | 0.342 |
| Moderate | 3 | 1.03 (0.76–1.40) | 56 | 16 | 1.01 (0.90–1.13) | 42 | ||
| Heavy | – | n.e. | n.e. | 10 | 0.95 (0.75–1.20) | 65 | ||
| Kidney | Light | 6 | 0.93 (0.85–1.02) | 37 | 11 | 0.92 (0.82–1.03) | 36 | 0.549 |
| Moderate | 6 | 0.74 (0.64–0.86) | 46 | 11 | 0.82 (0.72–0.94) | 32 | ||
| Heavy | 2 | 0.88 (0.16–4.92) | 81 | 3 | 0.81 (0.67–0.98) | 0 | ||
| Non-Hodgkin's lymphoma | Light | 9 | 1.02 (0.93–1.12) | 39 | 15 | 0.78 (0.69–0.88) | 46 | 0.360 |
| Moderate | 9 | 0.87 (0.77–0.97) | 36 | 15 | 0.88 (0.78–0.99) | 37 | ||
| Heavy | 3 | 0.74 (0.59–0.92) | 0 | 4 | 0.82 (0.60–1.13) | 50 |
Abbreviations: AC=adenocarcinoma; CI=confidence interval; n.e.= not evaluable; RR=relative risk; SCC=squamous cell carcinoma.
Only cancer sites for which more than 10 studies were available were considered.
a
Heterogeneity test.