Religion may appear to be a key component of addiction recovery programs like Alcoholics Anonymous but a new study suggests that these programs are just as effective for believers as they are for non-believers.

The most important predictor of success turned out simply to be going to the meetings. Alcoholics enrolled in AA and similar programs were more likely to abstain from alcohol completely than people who did not take part in support groups, and they drank less if they did return to the bottle. And those who attended the most meetings got the most benefit.

"If you don't go to any, you have the worst outcomes," said study lead author John Kelly, associate director of the Massachusetts General Hospital/Harvard Addiction Research Program. "If you go to a few, you have a little bit better outcome, and if you go to a lot, you have an even better outcome."

The study is among the first to examine the effectiveness of AA-type programs among different types of people.

Kelly and a colleague followed 227 alcoholics for up to three years after they left outpatient rehabilitation programs in Boston and Providence, R.I. They report their findings in the August issue of Alcoholism: Clinical and Experimental Research.

In groups such as AA, participants are urged to seek help from a "higher power." Even so, nonreligious people benefited as much from AA and similar programs as those who were religious, Kelly said. Men and women benefited equally, as did people with coexisting psychiatric illnesses.

AA and similar programs appear to work by providing "camaraderie and a support structure," said Aaron White, associate professor of psychiatry at Duke University and a specialist in addiction. "When you feel like drinking, you have a sponsor, someone in charge of keeping you from doing that. That's pretty powerful socially."