comment in the Guardian is headlined to say that psychological therapies are highly effective and save money. Steady on! As with medication, we all want a simple, quick, cheap, painless and complete cure of mental health problems. It's important to be hopeful about the outcome of treatment, but we also need to be realistic (eg. see previous blog entry How easy is it to treat depression?).
What Clark doesn't mention is the difficulty of measuring the effectiveness of psychological therapy. Expectancies affect the outcome of clinical trials and can't be controlled by double-blinding, as subjects know whether they receive the active treatment or are in the control group. There is a real issue about the adequacy of control groups (eg. see my BMJ letter).
His claim about saving money relates to the report from the Centre for Economic Performance. Lord Layard has been very influential in getting the Improving Access to Psychological Therapies (IAPT) initiative introduced into the NHS. We need evidence that IAPT has helped the economy before making such a claim.