Mental Health Literacy was defined as knowledge and beliefs about mental disorders that aid in its recognition, management or prevention. Portugal is the European country with the highest prevalence of mental illness in the population (22.9%) and anxiety disorders are the most common (16.5%). Approximately 20% of children and adolescents suffer from some mental disorder and about 8% of adolescents aged 13 to 18 years have some anxiety disorders. Portugal School Health Program 2015 evidences the promotion of health literacy and anxiety as areas of intervention in adolescence. The investigators intend to know the feasibility of a psychoeducational intervention to promote adolescents' mental health literacy (MHL) about anxiety in a school context.

Mental Health Literacy (MHL) was defined as knowledge and beliefs about mental disorders that aid in its recognition, management or prevention and include several components: recognition of disorders to facilitate help-seeking; knowledge of professional help and treatments available; knowledge of effective self-help strategies; knowledge and skills to give first aid and support to others, and knowledge of how to prevent mental disorders. MHL is not simply knowledge of mental health problems, it is knowledge linked to action which can benefit one's own mental health or that of others. Portugal is the European country with the highest prevalence of mental illness in the population (22.9%) and anxiety disorders are the most common (16.5%). Approximately 20% of children and adolescents suffer from some mental disorder and about 8% of adolescents aged 13 to 18 years have some anxiety disorders. In a Portugal recent study, anxiety predominated in 66.3% (930) adolescents between the ages of 13 and 17 who used the urgency of a pediatric hospital from 2011 to 2014. Portugal School Health Program (2015) evidences the promotion of health literacy and anxiety as areas of intervention in adolescence.

The objectives of this study are: identify adolescents' MHL about anxiety in school setting; design an psychoeducational intervention to promote adolescents' MHL about anxiety in school setting; validate the content of that intervention and evaluate its feasibility.

Research Method(s): Medical Research Council's (MRC) framework and CReDECI Checklist were applied on the development and evaluation of complex interventions using quantitative, qualitative and mixed methods. Ethical considerations have taken place.

Implementation Strategies for Findings: Development of psychoeducational intervention to promote adolescents' MHL about anxiety in school setting supported by Health Promotion Model of Pender; Conceptual Model of Health Literacy and Integrative Model of Behavioral Prediction. Systematic reviews about adolescents' MHL and about MHL interventions showed reduced mental health literacy of adolescents and suggest some methods and pedagogical techniques. We designed a mental health literacy psychoeducational intervention about anxiety on adolescents in a school context called "ProLiSMentAl" using different methods and pedagogical techniques, consist of 4 sessions of 90 minutes: 1) Improvement social anxiety recognition; 2) prevention strategies; 3) self-help strategies; 4) knowledge of first aid strategies and 5) knowledge of professionals and treatments available. Contextual factors and determinants of the setting in the modelling of the intervention were given by a focus group with 6 health and education experts and a focus group with 6 adolescents and an e-delphi with 25 experts. After nurses' training and preparation meetings, mixed studies were carried out to model the final intervention and determine feasibility, acceptability and practicability of this complex intervention: 1) feasibility study: pre-experimental, before and after, without control group with 11 adolescents; 2) adolescents', health and education professionals' evaluation; 3) pilot study: quasi-experimental, before, after and 1month follow-up (n=21) with an equivalent control group (n=17).

Inclusion Criteria:

All adolescents', students from 9th grade with informed consent.

Exclusion Criteria:

• students with special needs;
• students of other years of schooling
• students without informed consent.