Ten studies met the inclusion criteria (2,525 placebo and 3,325 aspirin) for stroke or death as the end point in both men and women (outcomes by sex unknown).
Eight studies met the inclusion criteria (2,244 placebo and 3,043 aspirin) for stroke or death as the end point in both men and women (outcomes by sex known).
Eight studies met the inclusion criteria (1,530 placebo and 2,161 aspirin) for stroke or death as the end point in men only.
Eight studies met the inclusion criteria (714 placebo and 882 aspirin) for stroke or death as the end point in men only.
All results are for risk reduction against stroke or death.
Men and women (no information on sex distribution): OR 0.83 (95% CI: 0.73, 0.95, p<0.01).
Men and women (outcomes by sex known): OR 0.82 (95% CI: 0.72, 0.94, p<0.01).
Men only: OR 0.82 (95% CI: 0.70, 0.96, p=0.01).
Women only: OR 0.82 (95% CI: 0.63, 1.05, p=0.12).
None of the tests for heterogeneity showed statistial significance, suggesting that observed results between studies did not vary excessively.