To understand a meta-analysis, best read the fine print.
The results of a meta-analysis are more than just the reported odds
ratio, 95% confidence interval, and P value. Of equal importance is the
fine print of the study which should include assessment of risk of bias,
certainty in evidence, and heterogeneity in the individual point
estimates and confidence intervals. These areas all have influence on
the quality of the data in the analysis. Reading and understanding the
fine print is important.