Background: In order to reduce the high prevalence of depression, early interventions for people at risk of depression are warranted. This study evaluated the effectiveness of an early guided self-help programme based on acceptance and commitment therapy (ACT) for reducing depressive symptomatology.
Method: Participants with mild to moderate depressive symptomatology were recruited from the general population and randomized to the self-help programme with extensive email support (n=125), the self-help programme with minimal email support (n=125) or to a waiting list control group (n=126). Participants completed measures before and after the intervention to assess depression, anxiety, fatigue, experiential avoidance, positive mental health and mindfulness. Participants in the experimental conditions also completed these measures at a 3-month follow-up.
Results: In the experimental conditions significant reductions in depression, anxiety, fatigue, experiential avoidance and improvements in positive mental health and mindfulness were found, compared with the waiting list condition (effect sizes Cohen's d=0.51-1.00). These effects were sustained at the 3-month follow-up. There were no significant differences between the experimental conditions on the outcome measures.
Conclusions: The ACT-based self-help programme with minimal email support is effective for people with mild to moderate depressive symptomatology.