I ran meta-analysis to combine findings of 15 studies. I used Comprehensive meta analysis software to generate the results. The purpose of the analysis is to see if the results are consistent and can support hypothesis in biology regarding one of the metabolites in the blood.
I calculated Q and I2 statistics and I found high heterogeneity between the studies (I2=86%). I did funnel plot and I found outliers. Removing two outliers from funnel plot and repeating I2 statistics yielded that I2 dropped to 0%
Is this the optimal way to evaluate heterogeneity in meta-analysis? If not, what is the correct and more robust method?