It is only ten years since the World Health Organization removed homosexuality as a diagnosis from the International Classification of Diseases. Homosexual men and women in the late 20th century were faced with a psychiatric profession that had long ago medicalised their sexuality.

But to treat something, you must have a concept of what that illness is. What models has medicine used? And what do they say about the way medicine and society interrelate?

Professor Michael King, Director of Department of Psychiatry and Behavioural Sciences at the Royal Free and University College Medical School, London, and his colleagues Dr Annie Bartlett and Professor Jeffrey Weeks, were awarded a History of Medicine project grant to study the history of treatments of homosexuality in Britain since 1950. Their study is an oral history of the period, recording the experiences and opinions of both the people who underwent treatments and the therapists who treated them. "We became aware of quite a lot of older people who had had treatment - either aversion therapy or more commonly psychoanalysis - to make them 'straight'."

The study addresses three key issues: "How did these people fare? How has the professionals' thinking evolved? And, finally, what does history tell us about what we are doing now - what are we medicalising now that we shouldn't be."

The project began with in-depth interviews with patients and professionals - psychologists and psychiatrists. "We knew largely where the professionals were, having previously done a historical review of British psychiatry and homosexuality. Some wouldn't be interviewed, or are still reluctant to come forward. But we came across a whole raft of people we didn't at first think of - the 'shadowy' people in the background, junior psychologists supervising treatment while the guru did all the research. They were often more interesting."

In the 1960s and 1970s, behaviourism came out of the laboratory into the clinic, offering aversion therapies to 'cure' homosexuality. Underlying these therapies was the idea that it was learned behaviour - and that you could unlearn it, or learn what you had missed out.

"The most striking thing was, what a Heath Robinson enterprise this was. A psychologist would get together some equipment and a slide projector in a dark room and shock the patient when he was looking at erotic pictures of men...there was a total, experimental blindness about it that you'd never get away with today, ethically."

Finding patients proved more elusive, although the project was advertised widely through the mainstream and gay press, on radio and TV. "We didn't find as many people as we thought, which has puzzled us. There may be a whole lot of ex-patients out there we're missing, but perhaps it wasn't as common as people thought."

"But I think the people we're really missing went into psychoanalysis, which was much more common. Five to 15 sessions of aversion therapy and hey presto! you're heterosexual - I'm caricaturing - but psychoanalysis was not so focused and patients may not have been aware of the analyst's aim [to help them reach the 'mature' stage of heterosexuality]."

Professor King is most interested in how older professionals now regard their work: "We wanted to know, how has this evolved in your head - have you learned anything, would you do it again? But my preliminary impression is that many are not nearly as insightful as I'd hoped. Some have been very upset by it, both at the time and now. But many look back on it as a kind of interesting 'experiment', where I think it was very doubtful - did they have any right to do it? Sadly, there's not much wisdom flying around, not much thinking what the therapy did to the people."

For Professor King, the lessons are clear. "We have to be careful looking back at events 30 years ago with today's eyes. However, it makes us think - what are we doing now that someone is going to question in 20 years? Are we again involved in social control - locking up 'undesirables', as the Government wants? Shouldn't we be thinking more carefully about what we're doing now?"

See also

• History of Medicine project grants: Background information

External links

• Department of Psychiatry and Behavioural Sciences at the Royal Free and University College Medical School: Affiliation of Professor Michael King
• International Classification of Diseases: provided by the World Health Organization
• British Journal of Psychiatry