The Big Question: Does cognitive therapy work – and should the NHS provide more of it for depression?

Why are we asking this now?

There is growing frustration among GPs at the difficulty they face in providing psychological therapy for patients with mental problems including depression. A survey by the Royal College of General Practitioners (RCGP) published at the weekend found almost two-thirds of respondents said they were "rarely" able to obtain treatment for patients within two months. Getting help for children who had suffered abuse or trauma was even more difficult. Professor Steve Field, the president of the RCGP, said: "People should have access to approved treatments, and this has to be a wake-up call."

Why is psychological treatment important?

Because, as Professor Field said, "if patients can't get access to talking therapies, then they will be on medication". A couple of decades ago, the advice to those who were depressed and out of work was to get "on yer bike". Today it is as likely to be to get on the couch.

What does this mean for patients?

Whereas in the past, GPs might have prescribed Prozac or other antidepressants, cognitive-behavioural therapy (CBT) is now the treatment of first choice – where it is available – for the millions who turn up complaining they cannot cope. In 2007, the Government earmarked £173m to train 3,600 extra therapists by 2010.

So why the shortage of therapists?

The cash is no longer ring-fenced and has allegedly been siphoned away to pay for other projects. The RCGP and Mind, the mental-health charity, are campaigning for a commitment from all three main political parties to ring-fence cash for talking therapies. The National Institute for Health and Clinical Excellence (Nice) says CBT should be the first-line treatment for mild to moderate depression, followed by drugs only if it proves unsuccessful.

What is the Government's response?

According to the Department of Health, more than 230,000 people have benefited from the extra therapists appointed since 2007, and almost three-quarters of primary care trusts now offer the service, up from a quarter two years ago.

What is cognitive therapy?

A mental technique in which patients are taught to break habitual ways of seeing things and to think positively. The aim is to help them replace dysfunctional thoughts such as "I knew I would never be able to cope with this job" with alternatives such as "The job is not going well, but I can work out a plan to deal with the problems." Negative thinking is very prevalent in Western societies, with their emphasis on competition and success.

Is it better than other forms of therapy?

It is often claimed that its advantages over other forms of therapy are that it is brief, it is direct and it works. It is one of the few therapies for which there is clinical evidence of its effectiveness. Instead of focusing on the causes of distress that may lie buried in the past, the therapy examines ways to improve the patient's state of mind now. A course of treatment would usually last for six to eight half-hour sessions with a trained counsellor.

But how effective is it?

Less so than its supporters think. Although approved by Nice, a review of 175 trials in the British Journal of Psychiatry published this month concluded that the effects had been exaggerated. Two-thirds of people (67 per cent) improved with therapy, which sounds impressive. However, 40 per cent improved without therapy. So the treatment delivered an extra 27 percentage-point "effect".

How has this been exaggerated?

By "publication bias". Publication bias occurs when publishers of medical journals choose to accept trials that show positive results and reject those that show zero or negative results. This skews the published literature to show a larger effect of the treatment than is true in reality. Pim Cuijpers from Vrije University, Amsterdam, who led the review, said that when publication bias is taken into account, it reduces the effect of CBT by "about one-third, to 18 per cent".

So is cognitive therapy worth having?

Probably, given the limited alternatives. Research on antidepressant drugs yields similar results to that for therapy – about two-thirds of patients feel better. But a controversial paper published in 2008 claimed publication bias was also responsible for exaggerating the effects of drugs. The review of 47 trials of six of the best-known antidepressant drugs, including trials that were unpublished, concluded the drugs were no better than placebos in most patients. Only in a very small group of the most extremely depressed were they more effective. The findings, by Professor Irving Kirsch of the University of Hull, published in the online journal Public Library of Science Medicine, have been challenged by a number of researchers.

Is cognitive therapy good for anything else?

Yes. Remarkably, it has been shown to be effective as a treatment for back pain. This is not because back pain is all in the mind but because CBT can help people manage the pain. A common problem among sufferers is that they think they have harmed themselves so they avoid activity and movement, and become de-conditioned and fearful of pain. They get into a vicious circle which CBT can help to break. An enhanced version of CBT has also shown promising effects in eating disorders by helping tackle problems such as low self-esteem and extreme perfectionism.

What other treatments are there for depression?

Regular exercise boosts self-esteem through improving body image or achieving goals, and by relieving feelings of isolation. It also releases feelgood brain chemicals such as endorphins. Nice says exercise should be combined with cognitive-behavioural therapy as the first line of treatment for mild to moderate depression.

Should we be avoiding antidepressants?

No. Depression can be a serious illness which destroys a person's quality of life and imposes a huge burden on them, their families and society. It causes more deaths, by suicide, than any other psychiatric disorder. In severe cases, drugs can be life-saving. In moderate cases, too, drugs can transform a person's outlook so that they are able to make changes to their life necessary to escape from depression, which seemed impossible while they were depressed. Depression has historically been under-treated and still carries a heavy burden of stigma, which means many people suffer rather than admitting they are ill and seeking treatment.

Is cognitive therapy the answer to depression?

Yes...

*It helps people counter negative thoughts and take control of their moods

*It does not have side effects and can be used if depression recurs

*It is recommended by Nice as the first-line treatment for sufferers

No...

*There are not enough cognitive therapists to meet the demand

*Its benefits have been exaggerated and it is less effective than claimed

*We will always need drugs for sufferers from severe depression