Previous research has noted trends of increasing internalizing problems (e.g., symptoms of depression and anxiety), particularly amongst adolescent girls. Cross-cohort comparisons using identical assessments of both anxiety and depression in youth are lacking, however. In this large twin study, we examined trends in internalizing symptoms in samples of 9 year old children and 15 year old adolescents, gathered from successive birth cohorts from 1998 to 2008 (age 9) and 1994–2001 (age 15). Assessments at age 9 were parent-rated, and at age 15 self- and parent-rated. We examined (i) the relation between birth cohorts and internalizing symptoms using linear regressions, and (ii) whether percentages of participants exceeding scale cut-off scores changed over time, using Cochrane Armitage Trend Tests. Among 9 year old children, a significantly increasing percentage of participants (both boys and girls) had scores above cut-off on anxiety symptoms, but not on depressive symptoms. At age 15, a significantly increasing percentage of participants (both boys and girls) had scores above cut-off particularly on self-reported internalizing symptoms. On parent-reported internalizing symptoms, only girls demonstrated a corresponding trend. In line with previous studies, we found small changes over sequential birth cohorts in frequencies of depression and anxiety symptoms in children. Further, these changes were not exclusive to girls.

中文翻译：

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儿童和青少年内在症状的趋势：来自瑞典人口的双生子队列的结果

先前的研究已经注意到内在化问题（例如抑郁症和焦虑症）的增加趋势，特别是在青春期女孩中。然而，缺乏对年轻人的焦虑和抑郁进行相同评估的跨队列比较。在这项大型的双胞胎研究中，我们研究了从1998年至2008年（9岁）和1994-2001年（15岁）连续出生的队列中收集的9岁儿童和15岁青少年的内在症状趋势。9岁时的评估为父母评估，而15岁时的自我评估和父母评估。我们使用Cochrane Armitage趋势检验研究了（i）使用线性回归的出生队列与内部症状之间的关系，以及（ii）超过量表临界值的参与者百分比是否随时间变化。在9岁的儿童中，参与者（男孩和女孩）的焦虑症状得分均高于临界值，但抑郁症状得分均未超过临界值。在15岁时，参与者（男孩和女孩）的分数显着增加，尤其是在自我报告的内在症状方面，分数都超过了临界值。在父母报告的内在症状上，只有女孩表现出相应的趋势。与以前的研究一致，我们发现连续的出生队列在儿童抑郁和焦虑症状的发生频率方面有微小的变化。此外，这些变化并非女孩所独有。特别是在自我报告的内在症状方面，参与者（男孩和女孩）的分数显着高于临界值。在父母报告的内在症状上，只有女孩表现出相应的趋势。与以前的研究一致，我们发现连续的出生队列在儿童抑郁和焦虑症状的发生频率方面有微小的变化。此外，这些变化并非女孩所独有。特别是在自我报告的内在症状方面，参与者（男孩和女孩）的分数显着高于临界值。在父母报告的内在症状上，只有女孩表现出相应的趋势。与以前的研究一致，我们发现连续的出生队列在儿童抑郁和焦虑症状的发生频率方面有微小的变化。此外，这些变化并非女孩所独有。