Exposure to adverse events as children -- including physical and emotional neglect, violence, and sexual abuse -- is strongly associated with adolescent depression and violence perpetrated by young people in poor urban areas around the world, including India, a study has found.

Based in multiple countries across five continents, the study, published in the Journal of Adolescent Health, found that boys are suffering even more than girls.

“This is the first global study to investigate how a cluster of traumatic childhood experiences known as ACEs, or adverse childhood experiences, work together to cause specific health issues in early adolescence with terrible, life-long consequences,” said Robert Blum, from the Johns Hopkins Bloomberg School of Public Health in the US.

“While we found young girls often suffer significantly, contrary to common belief, boys reported even greater exposure to violence and neglect, which makes them more likely to be violent in return,” Blum said.

The study catalogued the ACEs suffered by 1,284 adolescents aged 10 to 14 in 14 “low-income urban settings” around the world.

It found remarkably common experiences with trauma -- and very similar impacts -- regardless of where the children lived, which included Vietnam, China, Bolivia, Egypt, India, Kenya, UK and the US.

The report is the first to include an assessment of how adversity impacts young children in multiple low- and middle-income countries, where the vast majority of the 1.8 billion 10- to 24-year-olds worldwide live -- about a quarter of the global population.

The study found that 46 per cent of young adolescents reported experiencing violence, 38 per cent suffered emotional neglect and 29 per cent experienced physical neglect.

However, boys stood out in several categories. They were more likely to report physical neglect, sexual abuse and violence victimisation.

For both boys and girls, the more adversity they experienced, the more likely they were to engage in violent behaviours, such as bullying, threatening or hitting someone.

The effect of the adversity was more pronounced for boys than girls, with boys 11 times more likely to be engaged in violence, and girls four times more likely to be violent.

The study also found that, in general, the cumulative effect of their traumas tended to produce higher levels of depressive symptoms among girls than boys, while boys tended to show more external aggression than girls.

The study is part of the Global Early Adolescent Study, a major collaboration of the World Health Organization (WHO) and the Johns Hopkins Bloomberg School of Public Health to understand more about the development of gender stereotypes in early adolescence and their impact on adolescent health around the world.

It supports a key conclusion from a major new report to be released next week at Women Deliver in Vancouver, Canada based on a global coalition of adolescent health experts: that the world will never achieve gender equality “by focusing on girls and women alone and excluding boys and men.”

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