Characteristics | Categories | No. of Studies | Pooled OR (95% CI) | Heterogeneity test I2%, p-value | Differences between subgroups; χ2 test (p-value) |
---|---|---|---|---|---|
Overall | – | 20 | 18.56 (15.68–21.97) | 55.4%, P < 0.01 | – |
Sex | Male | 8 | 14.07 (10.46–18.93) | 49.0%, P = 0.06 | P = 0.06 |
Female | 8 | 21.47 (15.55–29.63) | 0%, P = 0.55 | ||
Study location | America | 5 | 15.69 (10.82–22.74) | 57.4%, P = 0.05 | P = 0.33 |
Asia | 9 | 21.00 (16.77–26.30) | 59.1%, P = 0.01 | ||
Europe | 6 | 17.23 (13.19–22.51) | 5.6%, P = 0.38 | ||
Development status | Developed countries | 10 | 17.31 (13.38–22.40) | 58.7%, P < 0.01 | P = 0.46 |
Developing countries | 10 | 19.73 (15.56–25.03) | 56.2%, P = 0.01 | ||
Lauren’s histological type | Intestinal type | 10 | 15.07 (9.55–23.78) | 62.0%, P < 0.01 | P = 0.27 |
Diffuse type | 10 | 10.69 (7.14–16.00) | 79.0%, P < 0.01 | ||
Tumor anatomical location | Cardia | 10 | 6.65 (5.18–8.52) | 21.8%, P = 0.24 | P = 0.46 |
Body | 10 | 6.31 (2.38–16.69) | 97.0%, P < 0.01 | ||
Antrum | 11 | 15.55 (4.12–58.62) | 98.2%, P < 0.01 | ||
Depth of invasion | Early | 3 | 5.87 (2.78–12.40) | 45.8%, P = 0.16 | P < 0.01†|
Advanced | 3 | 19.94 (13.31–29.85) | 22.9%, P = 0.27 | ||
Tumor stage | I + II | 2 | 33.50 (10.85–103.46) | 73.8%, P = 0.05 | P = 0.52 |
III + IV | 2 | 22.26 (13.05–37.96) | 24.6%, P = 0.25 | ||
Lymph node invasion | Absent | 3 | 16.98 (9.02–31.95) | 1.3%, P = 0.36 | P = 0.58 |
Present | 3 | 23.21 (9.44–57.03) | 80.6%, P < 0.01 |