Evaluating a brief imagery-based intervention for adolescent depression: study protocol for a Phase IIB randomised control trial (INDIGO) in secondary schools

There is an urgent need for psychological interventions that can target depression in late adolescence and prevent it from having lifelong implications. Schools have been identified as a promising setting to enhance access to interventions and offer support earlier. We have co-developed a novel intervention, IMAGINE, that targets key cognitive mechanisms implicated in depression across the lifespan. Depression has been associated with distressing negative mental images, a deficit in positive future images and overgeneral autobiographical memories. Interventions targeting these factors have shown clinical promise in adults. Here, we combine techniques targeting these cognitive processes into a novel, brief psychological intervention for adolescent depression. This Phase IIb randomised controlled trial will evaluate IMAGINE compared to an active psychological intervention.