Best paper I've read on the efficacy of AA-

http://hindsfoot.org/recout01.pdf

Basically, what Bill W. said decades ago still holds up. 3 or 4 out of 5 who initially come to a meeting don't stick. Maybe they come back later. Of those who stay and really try, about half achieve long term sobriety from the start. Another quarter make it after a slip or few.

Like I have observed, if you can tough it out for 3 months and get through a fourth and fifth step, you have a good chance at a sober, happy life. It works if you work it.