Guided self-help concreteness training as an intervention for major depression in primary care: a Phase II randomized controlled trial

Background. The development of widely accessible, effective psychological interventions for depression is a priority. This randomized trial provides the first controlled data on an innovative cognitive bias modification (CBM) training guided self-help intervention for depression. Method. One hundred and twenty-one consecutively recruited participants meeting criteria for current major depression were randomly allocated to treatment as usual (TAU) or to TAU plus concreteness training (CNT) guided self-help or to TAU plus relaxation training (RT) guided self-help. CNT involved repeated practice at mental exercises designed to switch patients from an unhelpful abstract thinking habit to a helpful concrete thinking habit, thereby targeting depressogenic cognitive processes (rumination, overgeneralization). Results. The addition of CNT to TAU significantly improved depressive symptoms at post-treatment [mean difference on the Hamilton Rating Scale for Depression (HAMD) 4.28, 95% confidence interval (CI) 1.29-7.26], 3- and 6-month follow-ups, and for rumination and overgeneralization post-treatment. There was no difference in the reduction of symptoms between CNT and RT (mean difference on the HAMD 1.98, 95% CI -1.14 to 5.11), although CNT significantly reduced rumination and overgeneralization relative to RT post-treatment, suggesting a specific benefit on these cognitive processes. Conclusions. This study provides preliminary evidence that CNT guided self-help may be a useful addition to TAU in treating major depression in primary care, although the effect was not significantly different from an existing active treatment (RT) matched for structural and common factors. Because of its relative brevity and distinct format, it may have value as an additional innovative approach to increase the accessibility of treatment choices for depression.