When is a meta-analysis conclusive? A guide to Trial Sequential Analysis with an example of remote ischemic preconditioning for renoprotection in patients undergoing cardiac surgery

Regardless of whether a randomized trial finds a statistically significant effect for an intervention or not, readers often wonder if the trial was large enough to be conclusive. To answer this question, we can estimate the required sample size for a trial by considering how commonly the outcome occurs, the smallest effect of clinical importance and the acceptable risk of falsely detecting or rejecting that effect. But when is a meta-analysis …