Community support for individuals with mental health problems is a global public health issue. Poor mental health literacy and high levels of stigmatising attitudes among the general population can hinder both help-seeking behaviours and limit the capacity of community members to provide support to people experiencing mental health challenges. The Mental Health First Aid (MHFA) training course was created to educate community members to provide initial help towards a person developing a mental health problem. MHFA training has spread to high-income countries, but there is relatively little research on cultural adaptation to lower-resource settings. This study aims to fill that gap and is the first cluster randomised controlled trial (cRCT) assessing the effectiveness of MHFA training in Chile and Argentina.

The study involves a two-arm wait-list cRCT with 240 participants (120 in each country). The study will be conducted in three settings in each of Chile and Argentina (eg, universities, health services and workplaces). Two clusters per setting in each country will be paired and randomly allocated to the intervention (the MHFA training for Chile and Argentina) or the wait-list control group. Participants in the intervention arm will be asked to complete questionnaires at baseline (T1), after training completion (T2) and 6 months after completion (T3), with control arm participants completing data collection at corresponding time points. The primary outcome will be intended support towards someone experiencing a mental health problem or experiencing a mental health crisis. Secondary outcome measures will include the ability to recognise depression and psychosis in vignettes; beliefs about the helpfulness of different types of interventions and helping actions, confidence in providing MHFA and stigmatising attitudes towards a person with depression or psychosis. Findings will demonstrate whether the culturally adapted MHFA training for Chile and Argentina can effectively enhance intended support, knowledge, attitudes and supportive actions towards other individuals within the community.

Ethics approval has been granted by the Human Research Ethics Committee at the University of Melbourne (Australia), Proyecto Suma (Argentina) and the University of Chile (Chile). Dissemination will be via academic publications and conference presentations. These will also be made available to participants and other interested parties on request.

ISRCTN63724445.