CBT is less effective – and nobody knows why.

CBT - now you need to have hope and trust that it works.

CBT – now you need to have hope and trust that it works.

A new meta-analysis of 70 studies of the effectiveness of cognitive behavioural therapy or CBT has concluded that over time it works less well.

Tom Johnsen and Oddgeir Friborg(pdf) looked at research involving 2426 patients with depression and compared the scores of their pre- and post-therapy questionnaires on two well known scales; the Beck Depression Inventory and the Hamilton Depression Rating Scale. When they looked at results from a period from 1977 to 2015, they found CBT does not help to reduce symptoms of depression as much as it used to.

The results of this study of course flashed around the world from the Huffington Post to the Guardian with journalists hungrily trying to explain the data. Oliver Burkeman speculated on the role of the placebo effect in therapy, others wondered if the clinical landscape had been flooded with rookie therapists who were basically doing it wrong. One interesting idea put forward was that all treatments, over time, gradually show worsening results.

The thing to note, as the BPS did, is that actually the authors of the original study were not able to answer the question of why, but were only able to offer speculations. Perhaps patients belief in the efficacy of CBT have decreased they said: “it is not inconceivable that patients’ hope and faith in the efficacy of CBT has decreased somewhat” The paper they had just written, they noted, might also help to erode patient’s faith in CBT.

The real news from this study appears to be the idea that a patient who receives CBT has to also believe it will work for it to be effective. This is surely a strange belief to have if you are a CBT therapist.

If you practice CBT, your working assumption is that thoughts cause feelings, and by changing one’s thoughts you can change how you feel. How many CBT therapists will now also inform their patients that, by the way, if you want to get better, you’ll need to have hope and faith that this will work?

CBT is presented as the “gold standard” for many mental health issues because it “works”. When was the last time your GP told you, when handing over a prescription for antibiotics, that you also need “hope and faith” that they will be effective? Could there be more to therapy than CBT has room for?