Background Adolescence is a crucial period for the acquisition of good mental health behaviours, which are the foundation for health and wellbeing in later life. Improved knowledge about mental health and improved help-seeking behaviours have been shown to lead to better mental health outcomes. Mental health literacy (MHL) is multifaceted (e.g., knowledge about symptoms, the stigma around mental health, good mental health practices, etc.). Measures are needed that can assess these different aspects of MHL. Measurement of mental health literacy is currently limited due to a lack of reported psychometric instruments with known psychometric properties. Given that most mental health problems start in early adolescence, a scale is needed that is reliable and valid in this age group. Methods The development and validation of the psychometric instrument (termed the Knowledge and Attitudes to Mental Health Scales: KAMHS) entailed two phases: 1) item generation based on an evidence-based intervention programme: The Guide; and 2) item reduction through exploratory factor analysis (EFA), and confirmatory factor analysis (CFA) for factor structure and psychometric assessment. Participants were 559 Year 9 pupils in secondary schools across Wales aged between 13 and 14 years. Results Results from the CFA indicated an acceptable fit of the model to the data. The KAMHS showed good internal constancy and moderate test-retest validity (.40–.64). Conclusions The final version of the KAMHS contains 50 items that are appropriate for use in children and adolescents. These results suggest that the KAMHS can be used over time to assess the efficacy of interventions aimed at increasing the mental health literacy of adolescent populations.

Background Adolescent mental health has become a public health concern as 10–20% of adolescents have experiences with mental health problems. Improving mental health education is critical to reducing stigma and improving access to appropriate care when needed. Here we examine the impact of a mental health literacy programme (Guide Cymru) in young adolescents in the UK. A randomised controlled trial assessed the effectiveness of the Guide Cymru intervention. Method A total of 1,926 pupils (860 males and 1066 females) aged 13–14 (year 9) took part in the study. The secondary schools were randomised into the active and control arms of the study. Teachers in the active arm of the study were trained on the Guide Cymru and then delivered the intervention to their pupils. Pupils in the active groups received six modules of mental health literacy (the Guide Cymru), and control schools received teaching as usual. Mental health literacy across several domains (e.g., knowledge, stigma, help-seeking intentions) were assessed both before and after the intervention. Data collection for the randomised controlled trial ran from September 2019 to March 2020. Multi-level modelling analysis was conducted to account for the clustered nature of the design. Results All aspects of mental health literacy, including mental health knowledge (g = 0.32), good mental health behaviours (g = 0.22), mental health stigmas (g = 0.16), intentions to seek help (g = 0.15), and avoidant coping (g = 0.14) improved after completing the Guide Cymru programme (ps < .001). Discussion The current study presents evidence for the Guide Cymru’s effectiveness in improving secondary school pupils' mental health literacy. We demonstrate that providing teachers with appropriate resources and training to deliver the Guide Cymru programme within their classrooms can improve the mental health literacy of pupils. These findings have important implications for the beneficial impacts the secondary school system can have on reducing the burden of mental health problems at a critical point in a young person’s life. Trial registration ISRCTN15462041. Registered 03/10/2019.

Background Adolescent mental health has become a public health concern as 10–20% of adolescents have experiences with mental health problems. Improving mental health education is critical to reducing stigma and improving access to appropriate care when needed. Here we examine the impact of a mental health literacy programme (Guide Cymru) in young adolescents in the UK. A randomised controlled trial assessed the effectiveness of the Guide Cymru intervention. Method A total of 1,926 pupils (860 males and 1066 females) aged 13–14 (year 9) took part in the study. The secondary schools were randomised into the active and control arms of the study. Teachers in the active arm of the study were trained on the Guide Cymru and then delivered the intervention to their pupils. Pupils in the active groups received six modules of mental health literacy (the Guide Cymru), and control schools received teaching as usual. Mental health literacy across several domains (e.g., knowledge, stigma, help-seeking intentions) were assessed both before and after the intervention. Data collection for the randomised controlled trial ran from September 2019 to March 2020. Multi-level modelling analysis was conducted to account for the clustered nature of the design. Results All aspects of mental health literacy, including mental health knowledge (g = 0.32), good mental health behaviours (g = 0.22), mental health stigmas (g = 0.16), intentions to seek help (g = 0.15), and avoidant coping (g = 0.14) improved after completing the Guide Cymru programme (ps < .001). Discussion The current study presents evidence for the Guide Cymru’s effectiveness in improving secondary school pupils' mental health literacy. We demonstrate that providing teachers with appropriate resources and training to deliver the Guide Cymru programme within their classrooms can improve the mental health literacy of pupils. These findings have important implications for the beneficial impacts the secondary school system can have on reducing the burden of mental health problems at a critical point in a young person’s life. Trial registration ISRCTN15462041. Registered 03/10/2019.