Community violence and adolescent mental health in Brazil In Brazil, child and adolescent mental health problems account for a substantial proportion of its burden of disease. Brazil also has strikingly high levels of community violence, both when compared to high-income countries and to other Latin American low- and middle-income countries, and is home to some of the most violent cities in the world. There is evidence that exposure to community violence is associated with high levels of mental health problems in high-income countries, especially among adolescents. However, very little research exists in Brazil on this and few policies or interventions are in place to specifically manage, reduce, and prevent the resulting mental illness burden.   This project aims to establish a UK-Brazil research network on community violence and mental health, to produce evidence on this under-researched topic of primary importance to LMICs generally, and LMICs in Latin America in particular, and lay the groundwork for future collaborative research. Our long-term goal is to reduce the burden of mental health problems associated with exposure to community violence among adolescents living in Brazil.  The projects will tackle four research activities: 1. Through secondary analysis of two existing longitudinal studies, from Pelotas in the south of Brazil, and Salvador in the northeast of Brazil, we will investigate the association between exposure to different types of community violence and depression, post-traumatic stress disorder (PTSD) and conduct problems among adolescents. 2. We will assess the feasibility of investigating the effect on mental health of violence-reduction policies in Brazil through data linkage of national routine datasets on community violence, mental health, and social policies. 3. We will develop new tools through pilot data collection. We will assess the validity of the International Trauma Questionnaire, a new tool for ICD-11 PTSD and complex PTSD diagnosis, and conduct qualitative work to refine a measure of community violence in Brazil. Primary data will be collected in the State of Sao Paulo, Brazil, in Embu, a violent municipality in the outskirts of Sao Paulo city, and a middle-sized city, Araraquara.  4. The organisation of a workshop in Brazil bringing together Brazilian and UK researchers, governmental officials, NGOs and local stakeholders in order to draft a consensus statement on the policies and interventions necessary to manage, prevent and diminish the mental health consequences of exposure to community violence among adolescents in LMICs. Furthermore, the workshop will represent an opportunity to draft a statement on the research priorities in the field, with a particular attention being paid to the cognitive, emotional-processing and neurological mechanisms underlying the association between violence and mental health.   This funding will represent an opportunity to bring Brazilian and UK researchers from different disciplines together in an "International Community Violence and Mental Health Research Hub", with the common aim of tackling a public health priority for the Brazilian population. The findings will fill an important gap in the literature concerning the impact of exposure to community violence and the development of mental health problems in adolescents, the event-specific consequences of community violence on mental health, as well as enabling the future investigation of the potential effectiveness of different policies to reduce adolescent mental health problems. Furthermore, findings will provide the basis for informed discussions on the future research agenda and policies on community violence and mental health, a major public health priority for the Brazilian population. The Global Challenges Research Fund (GCRF) supports cutting-edge research to address challenges faced by developing countries. The fund addresses the UN sustainable development goals. It aims to maximise the impact of research and innovation to improve lives and opportunity in the developing world.