Intra- and extra-familial adverse childhood experiences and a history of childhood psychosomatic disorders among Japanese university students.

Background: Japan has been witnessing a considerable increase in the number of children with psychosomatic disorders. The purpose of this study is to examine the relationship between the risk of psychosomatic disorder in adolescents and intra- and extra-familial adverse childhood experiences (ACEs).

Methods: A retrospective cohort study of 1592 Japanese university students (52% male, mean age 19.