Table 2.

Summary risk estimates (SRRs) and 95% CIs for all endpoints

EndpointsGroupsSRR (95% CI)I2Number of studiesa
Cancer incidenceAll studies0.69 (0.52–0.90)8819
Adjusted for BMI0.82 (0.70–0.96)7611
Adjusted for time-related bias0.90 (0.89–0.91)568
Prospective studies0.71 (0.47–1.07)8912
Randomized clinical trials0.95 (0.69–1.30)55
Cancer mortalityAll studies0.66 (0.54–0.81)217
Adjusted for BMI0.60 (0.45–0.80)05
Adjusted for time-related bias0.45 (0.16–1.26)03
Prospective studies0.48 (0.23–0.97)04
Single cancer sites
 BreastAll studies0.88 (0.75–1.03)6013
Adjusted for BMI0.82 (0.67–1.00)487
Adjusted for time-related bias0.94 (0.90–0.99)326
Prospective studies0.94 (0.90–0.99)447
 ColonAll studies0.80 (0.64–1.00)7612
Adjusted for BMI0.84 (0.50–1.40)816
Adjusted for time-related bias0.92 (0.85–0.98)243
Prospective studies0.82 (0.57–1.17)745
 ProstateAll studies1.06 (0.80–1.41)9112
Adjusted for BMI0.98 (0.68–1.40)556
Adjusted for time-related bias1.25 (0.87–1.80)966
Prospective studies0.93 (0.89–0.97)596
 PancreasAll studies0.75 (0.49–1.15)8411
Adjusted for time-related bias0.48 (0.16–1.43)835
Time-related unbiased0.77 (0.38–1.55)405
Prospective studies0.89 (0.61–1.29)806
 LiverAll studies0.47 (0.28–0.79)829
Adjusted for time-related bias0.65 (0.39–1.08)383
Prospective studies0.78 (0.72–0.85)525
 LungAll studies0.82 (0.67–0.99)575
Adjusted for smoking0.95 (0.82–1.11)575
Adjusted for time-related bias0.88 (0.81–0.95)363
Prospective studies0.97 (0.69–1.35)263
  • aEstimates may not correspond to number of studies.