Table 2.
Summary RR and 95%CI of the association between dietary protein intake and prostate cancer risk
| Subgroups | Number of studies | RR | 95%CI | P for trend | Heterogeneity test | |
|---|---|---|---|---|---|---|
| P | I2 (%) | |||||
| Overall | 12 | 0.993 | 0.930–1.061 | 0.841 | 0.656 | 0.0 |
| Protein type | ||||||
| Animal protein | 5 | 1.001 | 0.917–1.092 | 0.988 | 0.891 | 0.0 |
| Vegetable protein | 5 | 0.986 | 0.904–1.076 | 0.753 | 0.556 | 0.0 |
| Study design | ||||||
| Cohort | 8 | 1.080 | 0.964–1.209 | 0.184 | 0.670 | 0.0 |
| Case-control | 3 | 0.960 | 0.874–1.055 | 0.399 | 0.797 | 0.0 |
| RCT | 1 | – | – | – | – | – |
| Cancer type | ||||||
| Localized-stage disease | 2 | 1.263 | 0.953–1.674 | 0.103 | 0.508 | 0.0 |
| Advanced-stage disease | 3 | 0.973 | 0.745–1.272 | 0.843 | 0.703 | 0.0 |
| Geographic locations | ||||||
| Europe | 6 | 1.005 | 0.931–1.085 | 0.899 | 0.566 | 0.0 |
| America | 5 | 0.943 | 0.824–1.080 | 0.397 | 0.450 | 0.0 |
| Asia | 1 | – | – | – | – | – |
RR relative risk, CI confidence interval, RCT randomized controlled trial