Deliberate self-harm and psychological problems in young adolescents: evidence of a bidirectional relationship in girls.

The purpose of this study was to test the hypotheses that there is a bidirectional prospective relationship between mental health and deliberate self-harm, in the sense that (1) psychological problems are a risk factor for the development of self-harm; (2) self-harm is a risk factor for the development of psychological problems; and (3) the relative absence of psychological problems is a protective factor against the continued use of self-harm in adolescents who have started to harm themselves. This was studied in a community sample of 879 young adolescents by means of a 2-wave longitudinal design with a one-year interval, with self-harm measured by a nine-item version of the Deliberate Self-Harm Inventory (DSHI-9r) and psychological problems by the self-report version of the Strengths and Difficulties Questionnaire (SDQ). The hypothesis of bidirectional relationship between psychological problems and self-harm was supported among girls, but not among boys - although there was evidence of psychological problems as a risk factor of self-harm in boys, the converse was not the case. The relative absence of psychological problems was found to be a protective factor against self-harm only among boys, but not among girls. The results are discussed in terms of self-harm having a different role in the development of psychopathology among girls than among boys.