for total stroke, ischaemic stroke, and haemorrhagic stroke based on the reported events in the treatment and placebo groups. We used a fixed effects model (Mantel-Haenszel method) and random effects model (DerSimonian and Laird method) to investigate the effect of vitamin E on stroke across the trials and calculated pooled relative risks and 95% confidence intervals.22 We performed the Q test for heterogeneity23 and also calculated the I2 statistic.24 We used meta-regression to evaluate to which extent heterogeneity between study results is related to blinding strategy (open label v double blind), morbidity status of participants (primary v secondary prevention), and vitamin E dose (≤200 mg/day v >200 mg/day;