Background: To study predictors at age 3 and at age 12 for ideations and acts of deliberate self-harm at age 15 in a representative birth cohort.
Method: Information about ideations and acts of deliberate self-harm at age 12 and at age 15 was obtained from parents and children. Information about the child's problems was obtained at age 3 using the Child Behavior Checklist 2/3 (CBCL 2/3), and at age 12 with the CBCL and Youth Self-report (YSR). Furthermore, when the child was 12, mothers and fathers gave information about their own health, well-being and mental distress, and about family functioning measured with the Family Assessment Device (FAD).
Results: There was a significant increase in self-reported deliberate self-harm (ideations or acts) from age 12 to age 15, especially among girls (from 3% to 13%). Parent-child agreement on acts and ideations of deliberate self-harm was very low at both time-points (proportion of agreement 0.0-0.2). Self-reports of deliberate self-harm at age 12 independently predicted both acts and ideations of deliberate self-harm at age 15. Female gender, self-reports of internalizing problems and somatic complaints, parent reports of child's externalizing problems and aggressivity, mother's reports of her health problems, and living in nonintact family at age 12 independently predicted self-reported acts of deliberate self-harm 3 years later. Parent reports of child's learning difficulties, and self-reports of being bullied independently predicted ideations of deliberate self-harm at age 15. Parent reports of child's psychopathology at age 3 assessed with the CBCL 2/3 had no predictive association with ideation or acts of deliberate self-harm at age 15.
Conclusions: Acts of deliberate self-harm in mid-adolescence are due to an accumulation of earlier family and parental distress, and child's externalizing and internalizing problems. Information about deliberate self-harm at age 12 is an important warning sign of deliberate self-harm in mid-adolescence.