Adolescence and young adulthood are sensitive periods for the development of mental distress, and timely support can prevent early signs of distress from escalating. This review examines the effectiveness of early intervention and secondary prevention approaches for supporting the mental health and wellbeing of young people and rangatahi aged 12-24 years, with a particular focus on those experiencing low to moderate distress.

The review draws on a structured scan of published and grey literature, identifying 20 evaluation papers covering 16 interventions across therapy-based brief interventions, community-based services, e-therapy, digital tools and family-integrated approaches. Overall, the evidence suggests that many early intervention and secondary prevention supports, including brief and low-intensity approaches, can reduce distress and improve wellbeing, functioning and coping. Effects were most consistent for broad outcomes such as distress, wellbeing and functioning, while findings for anxiety and depressive symptoms were more mixed.

Accessibility, youth-friendly delivery, sustained engagement and co-design with young people emerged as important enablers of effectiveness. Culturally appropriate, co-designed and Indigenous-led approaches also appear important for improving acceptability and engagement for rangatahi Māori. However, the evidence base remains uneven, with a need for stronger evaluation of what works best, for whom and under what delivery conditions.