Studies have demonstrated that CBT works at least as well as antidepressants at reducing depression, perhaps even better (DeRubeis et al., 1999). However, it’s difficult for people with depression to access CBT due to lengthy waiting lists.

The Improving Access to Psychological Therapies (IAPT) scheme has had a major influence on waiting times for people with depression and anxiety in the UK. Despite this, one in five individuals are still waiting over a year to receive treatment (We Need to Talk Coalition, 2012). Sometimes individuals are never offered the therapy and even when it is available most people aren’t able to access the treatment at a suitable time and place.

Computerised cognitive behavioural therapy (CCBT) therefore appears to be an attractive option as it’s an accessible and cost-effective self-help treatment, suitable for many people who prefer to avoid the stigma and disclosure of sensitive information commonly incurred by seeing a therapist (Gega et al., 2004). The number of papers published on CCBT have markedly increased and to date, at least five meta-analyses have been conducted investigating the effectiveness of CCBT on adult depression. All of these showed that CCBT was beneficial with moderate effect sizes. So it seems so far, so good…

Recently, a meta-analysis was conducted by So and colleagues (2013) which re-evaluated the short-term effectiveness of CCBT and also investigated its long-term effects, functional improvement and dropout in adults with depression. Their findings were published in BMC Psychiatry. It shows that CCBT improves depressive symptoms in adults with depression in the short term. However, CCBT did not improve dropout rates, functioning or depressive symptoms in the long term.

Methods

The authors of the meta-analysis searched five databases: MEDLINE, PsycINFO, EMBASE, CENTRAL and CiNii. To be eligible for inclusion, all RCTs:

• Were published before 1st August 2011
• Investigated the effects of guided and unguided CCBT specific to depression
• Involved comparison with one or more control conditions
• Individuals had to be aged 18 or over and have depression
• Used reliable and standardised rating-scales equally at baseline and follow-up
• Had proper allocation, concealment, single or greater binding of outcome assessment
• Studies had to have a primary end point including a measure of depression at the outcome assessment immediately after intervention and long-term follow up (more than six months)

Studies were excluded if:

• Participants were inpatients
• Patients had severe symptoms from self-help intervention
• Participants had comorbidities including psychotic disorders, manic status, dementia and severe physical conditions

Out of 4,888 studies initially screened, fourteen studies and 2,807 participants met the inclusion criteria. Sixteen comparisons from these were used. There were more female than male subjects and their mean age ranged from 22.6 to 55 years. The majority of CCBT programmes were based on standard CBT, whilst combined CBT with other therapies was used in two trials. All studies used depression as the primary outcome and eight trials used the Beck Depression Inventory. Secondary outcome measures including functioning post-treatment and number of dropouts.

Cohen’s method was used and the standard mean difference for the overall pooled effects across the included studies was estimated with a random effects model.

Results

Here is what the authors found:

• There was a significant difference in depressive symptoms between CCBT and controls immediately following treatment (pooled SMD: -0.48 [95% CI -0.63 to -0.33] indicating a significant moderate effect
• There was no significant difference in long-term follow up at six months between CCBT and controls (pooled SMD: -0.05 [95% CI -0.19 to 0.09]
• There was no significant difference in improved functioning between CCBT and controls as the pooled SMD was -0.05 [95% CI -0.32 to 0.22]
• A significantly higher drop out rate was found for the CCBT group compared to controls.

Conclusions

The authors concluded:

Despite a short-term reduction in depression at post-treatment, the effect at long-term follow-up and the function improvement were not significant, with significantly high dropout. Considering the risk of bias, our meta-analysis implied that the clinical usefulness of current CCBT for adult depression may need to be re-considered downwards in terms of practical implementation and methodological study.

Limitations and summary

There were some methodological weaknesses in this research which may have impacted on its validity and reliability. Firstly, not all studies used the Beck Depression Inventory (BDI) as the primary outcome measure. There were also issues with publication bias, control conditions and imputation. These issues could have influenced the findings and possibly overestimated the effects of CCBT. Moreover, there were more female subjects included so this sample was not truly representative of the population.

This meta-analysis suggests that CCBT improves depressive symptoms in adults in the short-term. However, long-term effects and functional improvement were not significant and a substantial dropout rate was revealed for the CCBT group. These results do cast doubt on the practical application of the effects of current CCBT for adults with depression. Mental health professionals may not trust the evidence for CCBT and thus not feel as confident in offering this therapy to individuals due to the non-improvement in long-term effects and functioning, as well as the high dropout rate. In addition, healthcare providers may be reluctant to pay for CCBT due to these findings.

Nevertheless, CCBT may be useful as part of a Stepped Care Programme for individuals who are on long waiting lists for other effective evidence-based psychotherapies, such as cognitive behavioural therapy. This would enable them to still take an active role in their recovery as well as be “held” by mental health services. CCBT could then act as an extension of a clinician and mental health services as opposed to a replacement of these.

One other concern is that not everybody is computer literate – this is especially problematic for some of our older elves! As is always the case, more careful research is required in this area in order to understand the true effects and potential of CCBT. This could investigate the effects of CCBT on a less biased sample and involve utilising one measure to assess depression severity e.g. the BDI.

Links

So, M., Yamaguchi, S., Hashimoto, S., Sado, M., Furukawa, T.A. & McCrone, P. (2013). Is computerised CBT really helpful for adult depression? A meta-analytic re-evaluation of CCBT for adult depression in terms of clinical implementation and methodological validity (PDF). BMC Psychiatry, 13¸ 1-14.

We need to talk: getting the right therapy at the right time (PDF). MIND We Need to Talk Coalition, 2012.

DeRubeis, R. J., Gelfand, L. A., Tang, T. Z., et al. (1999) Medication versus cognitive behavior therapy for severely depressed outpatients: mega-analysis of four randomized comparisons. American Journal of Psychiatry, 156(7), 1007 -1013.

Services for Patients with Depression. Department of Health, Clinical Standards Advisory Group, 1999.

Gega, L., Marks, I. & Mataix-Cols, D. (2004). Computer-Aided CBT Self-Help for Anxiety and Depressive Disorders: Experience of a London Clinic and Future Directions (PDF). JCLP/In Session, 60(2), 147-157.