Table 2. Summary risk estimates of the overall and subgroup analyses on dietary zinc intake and pancreatic cancer risk.
| Subgroups | Number of cases | Number of studies | Risk estimate (95% CI) | Heterogeneity test | |
|---|---|---|---|---|---|
| I2 (%) | P-value | ||||
| All studies | 1659 | 7 | 0.798 (0.621–0.984) | 58.2 | 0.026 |
| Study design | |||||
| Prospective | 211 | 2 | 0.895 (0.556–1.441) | 0.0 | 0.787 |
| Case–control | 1448 | 5 | 0.773 (0.523–0.985) | 71.5 | 0.007 |
| Ethnicity | |||||
| American | 1071 | 3 | 0.729 (0.471–0.987) | 69.8 | 0.037 |
| European | 375 | 2 | 1.179 (0.730–1.904) | 19.7 | 0.264 |
| Mixed | 213 | 2 | 0.661 (0.380–1.151) | 30.0 | 0.232 |