Region and sex differences in constituent dopamine neurons and immunoreactivity for intracellular estrogen and androgen receptors in mesocortical projections in rats.
The prevalence of different types of dysfunction in school was assessed with the Boston Teacher Questionnaire, completed for 1923 children born 8 years earlier in a university-affiliated maternity hospital. Cluster analyses of 15 items on the questionnaire resulted in six two-item clusters and one three-item cluster that were identical for girls and boys. We identified children as having a syndrome if they possessed all features of the cluster-defined syndrome. The most prevalent syndrome, consisting of both daydreaming and distractibility items, occurred in 18.5% of boys and 11.5% of girls. Boys were also more likely than girls to be identified as having the reading syndrome (11.6% and 7.7%, respectively), the hyperactivity/impulsivity syndrome (6.1% and 1.5%), and the syndrome characterized by frustration intolerance and peer problems (9.5% and 4.0%). The prevalences of the remaining three syndromes were similar in both sexes (arithmetic, 11.3% and 10.3%; difficulty following instructions, 5.1% and 4.7%; and the tasks syndrome [characterized by impersistence/dependence/inflexibility], 5.5% and 5.4%). More than 40% of boys and girls with one syndrome also had another. The lower prevalences in this sample than in an earlier-born sample assessed with the same instrument were confined to boys. Reasons for this temporal decrease in one sex only remain obscure. Girls with the reading syndrome were 10 times more likely, and boys with the reading syndrome were five times more likely, than their peers to receive special services and to have repeated a grade.