Commentary: Advancing an implementation science agenda on mental health and psychosocial responses in war-affected settings: comment on trials of a psychosocial intervention for youth affected by the Syrian crisis - by Panter-Brick et al. (2018).

Syria's civil conflict has created the largest humanitarian disaster of our time, causing massive population displacement, tremendous exposure to trauma, and loss. Advancing the mental health and psychosocial responses of war-affected populations both during acute humanitarian emergencies and in post-conflict transition is imperative in forging a constructive implementation agenda. This study makes an important contribution in building evidence toward effective interventions to advance the mental health and well-being of those affected by the Syrian crisis. Using an innovative approach, this work demonstrates that a thoughtful, ethical, and scientifically valid trial can be carried out in the midst of mass displacement. Further research is urgently needed on the effectiveness of interventions for vulnerable populations, with a growing need to embed studies of evidence-based mental health interventions within humanitarian responses.