This paper summarises the findings from a literature review that sought to answer the following key questions:

• What is the psychological status and prevalence of different mental health and psychosocial-related challenges among adolescents in the study countries?
• What are the protective factors for adolescent mental health and psychosocial well-being in the study countries?
• What are the risk factors for adolescent mental ill-health and psychosocial distress in the study countries?

Key messages

• In both Tanzania and Viet Nam, mental health problems and poor psychosocial well-being are more prevalent among older adolescents aged 15 and above. Girls are more likely to experience mental health problems than boys, regardless of age.
• Protective factors include higher levels of family income, living with both parents and connectedness with caregivers. Social capital and inclusion, and school attendance are also protective.
• Socioeconomic drivers of poor psychosocial well-being include low or declining socioeconomic status and inability to meet basic needs. Country-specific drivers include the burden of needing to participate in income-generating activities (Tanzania) and migration (by parents or adolescents themselves) from rural to urban areas or to other countries in pursuit of economic opportunities (Viet Nam).
• Experience of bullying and discrimination also drives poor mental health among adolescents. In both countries, bullying and peer victimisation are associated with depression and suicidal ideation and behaviours – for victims but also for bullies. Adolescents may be discriminated against due to HIV-positive status (Tanzania), their sexuality or status as returning victims of human trafficking (Viet Nam).
• Physical violence, psychological maltreatment and neglect result in anxiety, depression and low self-esteem among adolescents. In Viet Nam, early marriage and forced school dropout result in feelings of social isolation for girls.
• In Viet Nam, poor psychosocial well-being is linked to access to modern technology and the risks of addictive online behaviours, particularly for boys; girls are more at risk from cyberbullying and stalking. However, Vietnamese adolescents also use technology to find support, relieve stress and connect with friends. There is little evidence from Tanzania on linkages between adolescents’ use of technology and their mental health.