Mental health problems in adolescents are increasing. Universal school-based interventions may play an important preventative role.

The aim of the Approaches for Well-being and Mental Health Literacy: Research in Education (AWARE) trial was to evaluate two universal, school-based interventions that previously yielded evidence of impact in other countries: Youth Aware of Mental Health (YAM) and The Mental Health and High School Curriculum Guide (The Guide).

AWARE was a multi-school, parallel group, cluster randomised controlled trial in English secondary schools. Schools were allocated on a 1:1:1 ratio to one of two interventions or a usual practice control group, balanced on current levels of mental health provision within schools, school location, deprivation and urbanicity. Eligible participants were pupils in schools across England in Year 9 (aged 13–14 years) at baseline. The statistician, quantitative data analyst and economist were masked. Primary outcomes were depressive symptoms measured with the Short Mood and Feelings Questionnaire for YAM and intended help-seeking, measured with the General Help Seeking Questionnaire for The Guide (both at 3–6 months).

153 schools were randomised, including 12 166 pupils (NYAM = 4028 pupils, Nguide = 3997 pupils, Ncontrol = 4141 pupils). We found that for YAM vs control (N = 5516) there was no improvement in depressive symptoms s.m.d. = 0.02; 95% CI –0.05 to 0.10), and for The Guide vs control (N = 5409) we found increased intended help-seeking compared with the control group (s.m.d. = 0.10; 95% CI 0.02 to 0.19). A notable minority of schools were unable to deliver YAM because of challenges in implementing it. Increased depressive symptoms scores were observed in both intervention conditions, compared with control at the longer-term follow-up.

The findings indicate that participating in The Guide is effective at improving intended help-seeking. However, due to the increases in depressive symptoms associated with each intervention at the long-term follow-up, further investigation of the potential negative impacts of these programmes is advised before further rollout in English schools.

Trial registration number: ISRCTN17631228.

AWARE (Approaches for Wellbeing and Mental Health Literacy: Research in Education) is a three-arm, parallel-group, cluster randomised controlled trial. It assessed the effectiveness of two interventions – the Youth Aware of Mental Health (YAM) programme and Mental Health and High School Curriculum Guide – in addressing emotional well-being, compared with usual practice, among year 9 students in England.

To evaluate the cost-effectiveness of YAM and The Guide to inform policy decisions regarding the implementation of these mental health interventions in schools.

Cost-effectiveness was assessed using self-reported information from participants in the trial at baseline and two follow-ups – at 3–6 months after the start of intervention, and at 9–12 months post-intervention. Quality of life was measured with the Child Health Utility Index. Intervention delivery costs were calculated with data provided by the delivery teams. Service use costs were calculated with a short version of the Client Service Receipt Inventory, with unit costs obtained from publicly available sources.

For both interventions, difference in outcomes (change in quality-adjusted life-years over time) between the intervention group and control group were close to zero, with the largest change being an improvement of 0.0055 quality-adjusted life-years at the second follow-up for students in schools randomised to YAM. Changes in costs were likewise small.

At first follow-up, neither intervention is likely to be considered cost-effective. At second follow-up, YAM has a high probability of being considered cost-effective, with an incremental cost-effectiveness ratio of around £23 000 per unit of improvement in the quality-of-life measure, which falls within the threshold (£20 000 to £30 000) as used by the National Institute for Health and Care Excellence.

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