I found this part of the intro to the study interesting "Religiosity, however,
is strongly and positively related with psychopathology, which
we reasoned would be negatively related to AA affiliation."
So, the premise is that those who are more religious are more likely to have mental illnesses. Personally, I would go so far as to say that many religions are manifestations of mental abnormalities. Some religions were created by mentally ill people, and many religions prey on people with mental issues to this day. I'm just surprised to see it stated as fact in this paper, and I think that in so stating this, the authors show bias from the beginning.
This also seems to mess with the conclusion of the study. The way I interpret it, AA works more for those who are religious, yet works less for those who have mental issues, and those people who are more religious are more likely to be the ones with mental issues. Seems like the two "conditions" (religiousity and pyschopathology) should cancel each-other out to a certain extent as they pertain to success in AA.
Please correct me if I'm wrong in my assumptions. No offense will be taken at any answer from which I might learn.