A new study indicates non-believers are more intelligent than the religious, but we already knew that!
[psypost.org]
Problem with the study is it only includes meta-analysis from USA and also no Eastern religions.
All it really tells us is that the sample is from representational sections of USA and of non-Eastern religion
The correlation is very weak—0.20
It means very little. In particular, you can not conclude that people are religious BECAUSE they lack intelligence.
You can study some characteristic of any two classes of people and almost inevitably one class will differ from the other by some small amount.