A study of 800 children by researchers from the University of Washington followed them from years one and two over the next seven years. The children filled out surveys that measured their levels of depression, anxiety and anti-social behaviour. Parents and teachers also filled out questionnaires about the children's anti-social behaviour, their ability to understand other people's feelings, to make new friends and to resolve conflicts. The parents filled out questionnaires about family and marital conflict, family stress and parental depression. Anti-social behaviour among girls and anxiety among both sexes in years one and two turned out to be the best predictors of adolescent depression but depression in years one and two was not predictive of depression later. The researchers thought that girls who were disturbed might show this through their behaviour at a younger age but then 'turn inwards' and become depressed as they got older.
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