An unfinished agenda on adolescent health: Opportunities for interventions.

The Millennium Development Goal era has resulted in improvements in maternal and child health worldwide. As more children are surviving past their fifth birthday, the population of adolescents is increasing. Adolescence is a time of significant developmental transition; adolescence sets the stage for adult health through risks taken and beneficial and detrimental habits that are formed and it is thus an optimal time to target health interventions. Beginning interventions in adolescence or even earlier in childhood maximizes the impact on the individual's health in adult life. Evidence suggests that interventions to promote sexual and reproductive health, physical activity and healthy lifestyle, mental health and wellbeing, safe and hazard-free environment, improving access to nutritious and healthy foods, and minimizing exposure to substance abuse can improve health outcomes in young adolescents. School-based delivery strategies appear to be the most highly evaluated for improving adolescent health; they have been used to deliver interventions such as sexual health, substance abuse prevention, and nutritional interventions. Use of social media and information technologies, cash transfers, social protection, and micro-finance initiatives are promising strategies; however, given the lack of rigorous evaluations, there is a need for further research. Additional research is also warranted to strengthen the evidence base by establishing causality, understanding the differential impacts of adolescent health in different contexts particularly in low- and middle-income countries. In addition, research and evaluation in the domain of adolescent health must focus on how to implement interventions effectively at-scale, sustain the impacts over time and ensure equitable outcomes.