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This is a plain English summary of an original research article. The views expressed are those of the author(s) and reviewer(s) at the time of publication.

For adults with obsessive compulsive disorder (OCD), behavioural therapy, cognitive therapy and antidepressants such as clomipramine all reduce symptoms and have good tolerability. The strongest evidence of effectiveness for children and young people with OCD is for cognitive behavioural therapy with or without the antidepressant sertraline.

Findings from this review generally support previously published NICE guidelines on the management of OCD, particularly for children and young people. The review had attempted to rank treatment strategies by effectiveness, tolerability and cost but was hampered by low quality evidence. Because each type of treatment was shown to be effective, side effect profile and personal preference will be most important in treatment choice.

The review did not look at therapies for different severities of OCD impairment so whether certain therapies are more effective for mild, moderate or severe impairment is unknown.


Why was this study needed?

OCD is the fourth most common mental disorder in the UK. It is estimated around 12 in every 1,000 people in the UK are affected by the condition equating to almost 750,000 people.

OCD symptoms can range from mild to severe. Some people with OCD may spend an hour or so a day engaged in obsessive compulsive thinking but for others the condition can be more debilitating.

Despite its prevalence, the disorder is under-recognised and under-treated. Several psychological therapies and drugs have been found to reduce OCD symptoms and increase quality of life but direct comparisons of these therapies is lacking. Cost-effectiveness data of treatments is also limited.


What did this study do?

This was a network meta-analysis of 86 randomised controlled trials (7,306 adults; 1,305 children and young people). It combined trials where treatments were compared directly (head to head) with trials of treatments compared with placebo controls (indirect comparisons).

Psychological interventions included behavioural therapy (exposure and response therapy), cognitive therapy and cognitive behavioural therapy. Drug interventions included any antidepressant with some action on the serotonin neurotransmitters such as selective serotonin reuptake inhibitors (SSRIs) and clomipramine. Controls included placebo pills, psychological placebo (such as supportive therapy) and waiting list.

The underlying trials in the review were not of high quality and prone to several biases in favour of the intervention. Over half did not include the people who dropped out of the study in their analysis. Most psychotherapy trials also included people taking medication and used waiting list controls. There was also wide variation between the studies which reduces the reliability of the pooled analyses, so the results should be viewed with some caution.


What did it find?

  • In adults, behavioural and cognitive therapies were more effective than psychological placebo according to average differences in scores on the Yale-Brown-Obsessive Compulsive Scale (range 0 to 40). Behavioural therapy reduced the mean difference [MD] by ‑10.33 (95% credible interval [CrI] ‑13.38 to ‑7.29) and cognitive therapy by MD ‑9.21, (95% CrI ‑13.10 to ‑5.34).
  • Cognitive behavioural therapy was no more effective than psychological placebo (MD ‑1.22 (95% CrI ‑5.54 to 3.03).
  • No SSRI is more effective than another and they were all moderately more effective compared to drug placebo with good tolerability (combined MD ‑3.49, 95% CrI ‑5.12 to ‑1.81). Clomipramine was also more effective than placebo but less tolerable than SSRIs (MD ‑4.72, 95% CrI ‑6.85 to ‑2.60). Studies of venlafaxine or hypericum (St John’s wort) were too small to provide conclusive results.
  • In children and young people (17 trials; 991 people) cognitive behavioural therapy combined with sertraline had the largest effect, with good tolerability. It appeared to be as effective as cognitive behavioural therapy alone but there were small numbers of people for each type of treatment or combination of treatments.
  • Results for cost-effectiveness were inconclusive.


What does current guidance say on this issue?

NICE’s 2005 guidance on OCD was placed on the static list in February 2014 as no major on-going studies were due to be published within the next three to five years. The decision will be reviewed in 2019.

The 2005 guidance recommends low intensity (up to 10 hours) cognitive behavioural therapy or behavioural therapy for adults with mild OCD. An SSRI, more intensive cognitive behavioural therapy or behavioural therapy is recommended if response is inadequate and for moderate OCD. Combined treatment is recommended for severe impairment.

For children and young people with mild OCD, guided self-help and support is recommended and cognitive behavioural therapy or behavioural therapy for moderate to severe impairment.


What are the implications?

Findings from this review generally support previously published guidelines on the management of OCD, that psychological therapies and SSRI drugs are of benefit either alone or in combination. There was insufficient evidence to reliably rank the different types of psychological therapies or drug treatments in order of likely success. This was partly due to the majority of psychological trials including people who were taking medications (mostly SSRIs). Therefore there is less certainty in the finding that behavioural therapy and cognitive therapy were more effective than medication because the way study was conducted may have favoured psychotherapies unfairly.

This means that treatments will continue to be chosen on an individual basis according to preferences, side effect profiles and comorbid conditions such as depression and anxiety.


Citation and Funding

Skapinakis P, Caldwell D, Hollingworth W, et al. A systematic review of the clinical effectiveness and cost-effectiveness of pharmacological and psychological interventions for the management of obsessive-compulsive disorder in children/adolescents and adults. Health Technol Assess 2016;20 (43).

This project was funded by the National Institute for Health Research Health Technology Assessment programme (project number 10/104/41).



NHS Choices. Obsessive compulsive disorder. London. Department of Health; updated 2014.

NICE. Obsessive-compulsive disorder and body dysmorphic disorder: treatment. CG31. London: National Institute for Health and Care Excellence; 2005.

Produced by the University of Southampton and Bazian on behalf of NIHR through the NIHR Dissemination Centre


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Selective serotonin reuptake inhibitors: These antidepressants include fluoxetine, sertraline, citalopram, escitalopram, paroxetine and fluvoxamine.

Clomipramine: An antidepressant that has some effect on the serotonin system but is classed as a tricyclic antidepressant. It therefore has other side effects such as a dry mouth, constipation, and blurred vision.

Yale-Brown-Obsessive Compulsive Scale and the Children’s Yale Brown-Obsessive Compulsive Scale: This scale combines scores for severity of obsessions and compulsions into a final score ranging from 0 to 40. The severity of OCD is considered subclinical (0 to 7), mild (8 to 15), moderate (16 to 23), severe (24 to 31) and extreme (32 to 40).

Trial biases: less than half of the adult trials reported results on an intention to treat basis, so most did not include drop-outs in their analysis which will bias results in favour of the intervention. In addition, several psychological trials were prone to subjective treatment bias as they compared the therapy to people on a waiting list so the participants were not blinded to whether or not they received an active treatment. Most of these trials were further biased as they included people who were already on an antidepressant.


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