Centre for Child and Adolescent Mental Health, Unifob Health, Bergen, Norway.
Soc Psychiatry Psychiatr Epidemiol. 2012 May;47(5):763-9. doi: 10.1007/s00127-011-0379-3. Epub 2011 Apr 16.
To estimate the prevalence of the ADHD phenotype based on parent and teacher reports in a general population sample of 7- to 9-year-old Norwegian children and evaluate the effect of parent attrition, gender and informant on the prevalence estimate.
The population consisted of all children (N = 9,430) attending 2nd-4th grade in the City of Bergen, Norway. The 18 symptoms of ADHD corresponding to the SNAP-IV and DSM-IV were included in the Bergen Child Study questionnaire to teachers and parents. Teacher information was available for 9,137 children (97%) and information from both informants was available for the 6,237 children (66%) whose parents agreed to participate in the study.
The prevalence of the ADHD phenotype based on the combination of parent and teacher reports was 5.2% among participants. Teacher ratings of non-participants had a doubled rate of ADHD high scorers with an OR of 2.1 (95% CI, 1.9-2.4). The non-participant ADHD high scorers had more inattentive and fewer hyperactive/impulsive symptoms as compared to participating ADHD high scorers. Teachers reported high scores of hyperactivity/impulsivity and the combined symptom constellation much more frequently in boys than girls, while the difference between genders was less marked according to parent reports.
The ADHD phenotype was twice as prevalent among non-participants as among participants. Reported prevalences in population studies are therefore likely to be underestimates, if such attrition bias is not accounted for. Choice of informant, criteria for symptom count, definitions of subtypes and gender differences influence the prevalence estimates of the ADHD phenotype.
根据家长和教师对挪威 7-9 岁普通人群样本的报告，估计 ADHD 表型的患病率，并评估家长流失、性别和信息提供者对患病率估计的影响。
该人群包括挪威卑尔根市所有 2-4 年级的儿童（N=9430）。SNAP-IV 和 DSM-IV 对应的 ADHD 18 种症状被纳入卑尔根儿童研究问卷中，供教师和家长填写。9137 名儿童（97%）提供了教师信息，而 6237 名（66%）父母同意参与研究的儿童则同时提供了来自两个信息提供者的信息。
根据家长和教师报告的综合结果，参与者中 ADHD 表型的患病率为 5.2%。未参与者的教师评分中 ADHD 高分者的比率增加了一倍，OR 为 2.1（95%CI，1.9-2.4）。与参与的 ADHD 高分者相比，未参与者的 ADHD 高分者的注意力不集中症状更多，而多动/冲动症状更少。教师报告男孩的多动/冲动症状和综合症状更为常见，而根据家长报告，性别差异则不那么明显。
未参与者的 ADHD 表型患病率是参与者的两倍。如果不考虑这种流失偏差，人群研究中报告的患病率可能会被低估。信息提供者的选择、症状计数标准、亚型定义和性别差异都会影响 ADHD 表型的患病率估计。
