Global mental health: trauma and adversity among populations in transition

M igration and trauma is a critical and timely area of inquiry given the enormous transna-tional migration occurring within the past year. The UN estimates there are over 244 million people living outside of their country of origin (United Nations Population Fund, 2016). United Nations High Commissioner for Refugees (UNHCR) estimated there were over 1,000,000 refugees fleeing to Europe by boat during the year 2015 (UNHCR, 2016). The nature of their migration is forced and due to war and violence in their home countries (e.g., Turner, 2015). Studies indicate that refugee communities are at increased risk for common mental disorders including posttraumatic stress disorder (PTSD), depression, and anxiety (Lindert, Von Ehrenstein, Priebe, Mielck, & Brähler, 2009). Therefore, the mental health of this sizable population in Europe and in other countries in the Middle East and globally is an important public mental health priority. Traumatic event exposure may occur during three key phases: pre-migration, transit, and post-migration (Zimmerman, Kiss, & Hossain, 2011). Continued research into the consequences of trauma exposure along this continuum, and intervention and prevention programs addressing the mental health of individuals and communities in transition are needed. This special issue of the European Journal of Psy-chotraumatology offers a collection of papers that focus on migrating populations experiencing trauma and adversity. These papers focus on several key issues facing migrant populations including anthropometric indicators of children exposed to violence in South Africa (Koen et al., 2016); the effects of acculturative stressors on refugees in Australia and Austria (Kartal & Kiropoulos, 2016); social integration and psychological impairment in traumatized refugees (Schick et al., 2016); prevalence of PTSD and depression among Iraqi Yazidi refugees (Tekin et al., 2016); organized violence as predictors of aggression and violent behaviors among refugees (Mueller-Bamouh, The paper by Koen et al. (2016) examined the associations between maternal trauma and posttraumatic stress disorder and adverse birth outcomes among 544 motherÁ infant dyads in the Drakenstein Child Health Study in South Africa. The results of their study indicated that an estimated prevalence of current and lifetime posttraumatic stress disorder was 19% and that showed that recent life stressors were associated with PTSD. Mothers' traumatic event exposure was significantly associated with reduced infant head circumference, indicating that trauma affected fetal growth and development. This study importantly illustrates the potential for intergenerational effects of trauma on a population in transition. Tekin and colleagues contribute a novel investigation into gender-based differences …