A long-term study of 900 families in Norway followed children from 18 months through to adolescence looking into the causes of childhood anxiety and depression. 10-20% of all children and young people will, in the course of growing up, display enough symptoms of anxiety and depression to qualify for a diagnosis. Maternal distress symptoms, family stress and a lack of support in the child's pre-school environment all led to an increase in depression and anxiety symptoms at 12-13. Girls were more likely to develop emotional problems at 12-13 than boys. They were more likely to churn problems over and could be more vulnerable as they go through puberty earlier than boys. Timid and shy children were at a greater risk of developing depression and anxiety. Timid/shy children who were inactive were at three times the risk of developing depression and anxiety than timid/shy children who were active.
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