Cognitive-behavioral therapy (CBT) is widely researched and recommended as an evidence-based treatment for adult depression, but despite the strength of research comparing CBT approaches with other forms of care, there are few recent systematic reviews on this topic.
Cuijpers and collaborators provide such a review in a recent meta-analysis published in The Canadian Journal of Psychiatry, where they examine the efficacy of CBT for adult depression, both alone and in combination with other treatments.
The authors included randomised clinical trials in adults, comparing CBT with a control intervention (wait-list, treatment as usual, placebo or other) or with another form of treatment (psychotherapy or medication). Studies were included if the primary clinical problem being treated was depression, evaluated either by a diagnostic interview or by self-report scales. Studies comparing the combination of CBT and pharmacotherapy with pharmacotherapy alone were also included.
Two independent raters evaluated included studies for methodological quality, using four criteria from the risk of bias assessment tool developed by the Cochrane Collaboration:
- Adequate sequence generation
- Allocation concealment
- Blinding of outcome assessors
- Incomplete outcome data
Effect sizes (ES) were calculated for each comparison between CBT and another group at post-test (standardised mean difference) and then transformed into Hedges’ g in order to adjust for bias due to small size (.20, .50 and .80 correspond to small, moderate and respectively large ES). The standardised mean difference was also transformed in an index more amenable to clinical interpretation, the NNT, indicating the number of patients that have to be treated to generate one additional positive outcome.
115 studies met the inclusion criteria and were included in the meta-analysis.
- CBT vs control (wait-list, treatment as usual, placebo or other):
- The mean ES (g) was 0.71 (95% CI 0.62 to 0.79)
- Corresponding to a NNT of 2.60
However, it is important to note that the authors evidenced considerable publication bias (confirmed by three methods), and also that study quality was a significant moderator of the results, with ES decreasing with the increase of study quality (a decrease of .14 with each of the quality criteria that was not met).
Additionally, effect sizes were smaller in clinical samples in studies conducted in the United States (as opposed to other countries), and in comparison with placebo and (or) other control groups, different than treatment as usual or waitlist.
- CBT plus pharmacotherapy vs pharmacotherapy:
- The mean ES (g) was 0.49 (95% CI 0.29 to 0.69)
- Corresponding to an NNT of 3.68
- CBT vs pharmacotherapy:
- The mean ES (g) was 0.03 (95% CI –0.13 to 0.18, P > 0.05)
- Indicating no significant overall difference in outcomes
- CBT vs other psychotherapies:
- The ESs ranged from -0.02 to 0.25 and were all non-significant
- But for some of the alternative forms of therapy considered, there were only a small number of RCTs comparing them with CBT
The authors conclude that:
Based on a large number of comparisons of CBT with a control or alternate intervention group, our meta-analysis found that CBT is an efficacious treatment for adult depression.
However they also add:
This effect size is an overestimation of the true ES, because we also found clear indications for publication bias. Further, the inclusion of a considerable number of lower quality studies has probably also led to an overestimation of the mean ES.
Other important conclusions:
- The combination of CBT and pharmacotherapy was superior to pharmacotherapy alone for the treatment of adult depression
- However, in contrast to previous meta-analysis, Cuijpers et al found no difference in efficacy between CBT and pharmacotherapy
- Comparisons with other forms of psychotherapy indicate CBT is no less and no more efficient, but for some of these forms of psychotherapy there are only a few studies comparing them with CBT
- The methodological quality of many of the studies included in the meta-analysis was subpar, with only 37% (43/115) of the studies meeting at least 3 of the 4 quality criteria
- Although the number of included studies was substantial, some of the subgroup contrasts were based on a small number of studies, which may have contributed to the failure to show significant differences between subgroups of studies
- The meta-analysis only examined the short-term outcomes of CBT
Cuijpers, P., Berking, M., Andersson, G., Quigley, L., Kleiboer, A., Dobson, K.S., 2013. A meta-analysis of cognitive-behavioural therapy for adult depression, alone and in comparison with other treatments. Can J Psychiatry 58, 376–385. [PubMed abstract]
A meta-analysis of cognitive-behavioral therapy for adult depression: the winner takes it all?: Cognitive-beha… http://t.co/dTnFIk1Dq6
@Mental_Elf Let us hope #NICE take notice of these conclusions and facilitate access to other psychological therapies.
Interesting findings re study quality & pub bias MT @Mental_Elf: Meta-analysis of CBT for adult depression: http://t.co/bJSxiG7pQd
@Mental_Elf or another case of garbage in – garbage out? #CBT on #NHS is certainly getting to that stage and that’s if you manage to get it
Debut blog from @Zia_Julia summarising a recent review which examines the efficacy of CBT for adult depression http://t.co/fKxZi3XvyB
Excellent blog-should we start questioning CBT’s ruling status? @Mental_Elf by @Zia_Julia CBT efficacy for depression http://t.co/p0h1E4HRCW
@dr_know @Mental_Elf @Zia_Julia I think plenty folk already are questioning it – good to see more research backing up service users’ doubts!
@hannahhypno @Mental_Elf @Zia_Julia think some service users really benefit from it, but evidence base overstated, alternatives neglected?
@dr_know @Mental_Elf @Zia_Julia Definitely. Just because it’s easy to quantify doesn’t make it the only way!
@dr_know @Mental_Elf @Zia_Julia How much recovery is actually down to the quality of the therapeutic relationship?
@121Therapy @Mental_Elf @Zia_Julia lots of evidence for so-called ‘common factors’ in therapy (eg. Therapeutic alliance, empathy).
A meta-analysis of cognitive-behavioral therapy for adult depression: the winner takes it all? http://t.co/3xJxKCZbsj via @sharethis
A meta-analysis of cognitive-behavioral therapy for adult depression: the winner takes it all? -… http://t.co/MWGDHsCUKj
A meta-analysis of cognitive-behavioral therapy for adult depression: the winner takes it all? http://t.co/IYfFspDo5l via @Mental_Elf
” A meta-analysis of cognitive-behavioral therapy for adult depression: the winner takes it all? http://t.co/s9jPcSgEQZ“
New meta-analysis of CBT vs antidepressants vs other talking treatments for depression http://t.co/fKxZi3XvyB
@Mental_Elf do you have any info on EYe movement threapy
New meta-analysis (via @Mental_Elf) indicates no difference in efficacy between CBT & pharmacotherapy for depression http://t.co/V0weoml9nw
Meta-analysis: CBT vs antideprss vs other talking Txs for depression http://t.co/NFh7GvtrKz via @PsychiatrySHO Large CBT pub bias & no diffs
Depression meta analysis – Minority (37%) of the studies met at least 3 of 4 quality criteria used http://t.co/mcGzdYD7eX
RT @Mental_Elf: Meta-analysis concludes that publication bias means we are overestimating the effectiveness of CBT for depression http://t.…
Meta-analysis of cognitive-behavioral therapy for adult depression: the winner takes it all? http://t.co/1rlo2onmpp
@Mental_Elf @AlieshiaCBT https://t.co/5pCKUbsp20 The comments after the “however”s indicates loser takes all. Damned with faint praise.
@bdocs @Mental_Elf I guess what I take from it is that CBT is still an effective therapy but it’s not the only one.
In case you missed it: A meta-analysis of cognitive-behavioral therapy for adult depression: the winner takes it all? http://t.co/fKxZi3XvyB
@Mental_Elf Recent meta-analyses, from Cuijpers & lot of other researchers, are clear: The Dodo Bird verdict (for depression) is +/- a fact.
@Mental_Elf …different psychotherapeutic interventions for depression have comparable, moderate-to-large effects… http://t.co/L9uU883AQP
Mental Elf: A meta-analysis of cognitive-behavioral therapy for adult depression: the winner takes it all? http://t.co/C5pqfxfcbx
Wow! Yesterday’s blog on questioning CBT’s ruling status has had a fantastic response http://t.co/fKxZi3XvyB Congats @Zia_Julia
Most popular blog this week: @Zia_Julia Publication bias & overestimating the effectiveness of CBT for depression http://t.co/fKxZi3XvyB
@Mental_ELF I am having a hard time finding out if the Meta considered only individual therapy or group therapy as well because the appendix is not published with the article. Do you have access to the appendix or know the what designs they included?
[…] psychotherapy, CBT has nonetheless been been shown to have some problems (see my previous blogs on CBT for adult depression and wait-list control exaggerating the efficacy of […]