NEW YORK (AP) – The American Psychological Association declared last week that mental health professionals should not tell gay clients they can become straight through therapy or other treatments.

In a resolution adopted by the APA's governing council, and in an accompanying report, the association issued its most comprehensive repudiation of "reparative therapy" – a concept espoused by a small but persistent group of therapists, often allied with religious conservatives, who maintain gays can change.

No solid evidence exists that such change is likely, says the resolution, adopted by a 125-4 vote. The APA said some research suggests that efforts to produce change could be harmful, inducing depression and suicidal tendencies.

Instead of seeking such change, the APA urged therapists to consider multiple options – that could range from celibacy to switching churches – for helping clients live spiritually rewarding lives in instances where their sexual orientation and religious faith conflict.

The APA had criticised reparative therapy in the past, but a six-member task force added weight to this position by examining 83 studies on sexual orientation change conducted since 1960. Its report was endorsed by the APA's governing council in Toronto, where the 150,000-member association's annual meeting was held at the weekend.

The report breaks new ground in its detailed and nuanced assessment of how therapists should deal with gay clients struggling to remain loyal to a religious faith that disapproves of homosexuality.

Judith Glassgold, a Highland Park, New Jersey., psychologist who chaired the task force, said she hoped the document could help calm the polarised debate between religious conservatives who believe in the possibility of changing sexual orientation and the many mental health professionals who reject that option.

"Both sides have to educate themselves better," Glassgold said in an interview. "The religious psychotherapists have to open up their eyes to the potential positive aspects of being gay or lesbian.

Secular therapists have to recognise that some people will choose their faith over their sexuality."

In dealing with gay clients from conservative faiths, says the report, therapists should be "very cautious" about suggesting treatments aimed at altering their same-sex attractions.

"Practitioners can assist clients through therapies that do not attempt to change sexual orientation, but rather involve acceptance, support and identity exploration and development without imposing a specific identity outcome," the report says.

"We have to challenge people to be creative," said Glassgold.

She suggested that devout clients could focus on overarching aspects of religion such as hope and forgiveness to transcend negative beliefs about homosexuality, and either remain part of their original faith within its limits – for example, by embracing celibacy – or find a faith that welcomes gays.

One of the largest organisations promoting the possibility of changing sexual orientation is Exodus International, a network of ministries whose core message is "Freedom from homosexuality through the power of Jesus Christ."

Its president, Alan Chambers, describes himself as someone who "overcame unwanted same-sex attraction." He and other evangelicals met with APA representatives after the task force formed in 2007, and he expressed satisfaction with parts of the report that emerged.

"It's a positive step – simply respecting someone's faith is a huge leap in the right direction," Chambers said.

"But I'd go further. Don't deny the possibility that someone's feelings might change."