(PhysOrg.com) -- Past behavior is generally considered to be a good predictor of future behavior, but new research indicates that may not be the case in the development of depression, particularly among adolescent girls.
University of Washington social scientists tracked first- and second-graders for seven years and found that anti-social behavior among girls and anxiety among both sexes predicted depression in early adolescence. Surprisingly, early signs of depression were not predictive of adolescent depression.
"Anti-social behavior has typically been viewed as a big problem among boys, so it tends to be ignored among girls. Boys with early anti-social behavior typically go on to show more anti-social behavior while girls may turn inward with symptoms, morphing into other mental health problems such as depression eating disorders, anxiety and suicidal behavior during adolescence ," said James Mazza, a UW professor of educational psychology and lead author of the new study. He is currently serving as the past president of the American Association of Suicidology.
"When all the risk factors were analyzed, anti-social behavior and anxiety were the most predictive of later depression. It just may be that they are more prevalent in the early elementary school years than depression." He noted that depression and anxiety share a number of symptoms.
Mazza said that early adolescence is when the first episode of depression typically occurs and that's when it has been noted that gender difference occur, with more girls than boys experiencing depressive symptoms. Children can be assessed at 6 and 7 years of age, but depression is not often recognized or diagnosed until the middle school years.
Children in this study were drawn from a larger project looking at the risks for health and behavior problems. That project was conducted by the university's Social Development Research Group, with which Mazza is affiliated. More than 800 children participated in the depression study. Eighty-one percent were white and 54 percent were boys.
Data were collected annually from the children and their parents and teachers when the children were in the first or second grade. The children filled out surveys that measured their levels of depression, anxiety and anti-social behavior, as well as other measures that were not investigated in this study. Parents and teachers filled out questionnaires about the children's anti-social behavior and social competency, which measured such things as the youngsters' abilities to understand other people's feeling, to make new friends and resolve conflicts. Teachers also rated each child's academic performance. In addition, parents filled out questionnaires concerning family and marital conflict, family stress and parental depression.
"One finding from this study that is a mind-grabber is that young children can identify themselves as being anxious and depressed," said Mazza. "When they had scores that were elevated we were a bit surprised because we thought they would say, 'My life is fun and I play a lot.' But they are able to understand and report feeling depressed or anxious, and tell us so. This suggests giving health surveys in early elementary school is a good idea and we should talk to kids in the first and second grades because they can give us valuable information."
Provided by University of Washington
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