Deng Qigang, Coleman Jonathan R I, Mottershead Ethan, Ronald Angelica, Zavos Helena M S, Kuntsi Jonna
Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.
National Institute for Health and Care Research Maudsley Biomedical Research Centre, South London and Maudsley NHS Foundation Trust, London, United Kingdom.
JAACAP Open. 2024 Feb 5;2(3):199-207. doi: 10.1016/j.jaacop.2024.01.004. eCollection 2024 Sep.
Being among the youngest in a school class increases the risk for worse educational outcomes and attention-deficit/hyperactivity disorder (ADHD) symptoms, but questions remain about the nature and persistence of such effects. We investigated this "relative age effect" on educational achievement at age 15 to 16 years and on ADHD symptoms from age 7 to age 21 years. Furthermore, we examined whether being young-in-class is linked to a greater reduction in ADHD symptoms from childhood to adulthood and a lower genetic propensity to ADHD.
We identified 3,928 young-in-class and 4,580 old-in-class participants from the Twins' Early Development Study. Educational achievement was measured with mathematics and English examination grades at age 15 to 16 years, and ADHD symptoms were measured using 2 different scales and different raters, from age 7 to 21 years, with effects tested using regression.
A relative age effect emerged for English but not mathematics examination grades, and for the majority of parent and teacher ratings on ADHD symptoms, most consistently in middle childhood. Being young-in-class was associated with a greater reduction in parent-rated ADHD symptoms from childhood to adulthood when measured with a brief scale, but the comparable result from a longer scale was non-significant (after multiple testing correction). No interaction emerged between relative age and ADHD polygenic scores.
Our results emphasise the need to improve support for the children who start school younger than most, and to ensure that developmental comparisons take children's precise age into account. Future research would benefit from in-depth analyses of individual trajectories and their variability among the young-in-class children.
在班级中年龄最小会增加教育成果较差和注意力缺陷多动障碍（ADHD）症状的风险，但此类影响的性质和持续性仍存在疑问。我们调查了这种“相对年龄效应”对15至16岁时教育成就以及7至21岁时ADHD症状的影响。此外，我们还研究了班级中年龄较小是否与从童年到成年期ADHD症状的更大程度减轻以及较低的ADHD遗传倾向有关。
我们从双胞胎早期发展研究中确定了3928名班级中年龄较小的参与者和4580名班级中年龄较大的参与者。使用15至16岁时的数学和英语考试成绩来衡量教育成就，使用两种不同的量表和不同的评估者对7至21岁时的ADHD症状进行测量，并通过回归分析来检验影响。
在英语考试成绩方面出现了相对年龄效应，但数学考试成绩未出现；在大多数家长和教师对ADHD症状的评分中也出现了相对年龄效应，最一致地出现在童年中期。当使用简短量表测量时，班级中年龄较小与从童年到成年期家长评定的ADHD症状有更大程度的减轻相关，但使用较长量表得出的可比结果不显著（在进行多重检验校正后）。相对年龄与ADHD多基因得分之间未出现交互作用。
我们的结果强调需要改善对那些比大多数人入学年龄更小的儿童的支持，并确保在进行发展比较时考虑儿童的确切年龄。未来的研究将受益于对个体轨迹及其在班级中年龄较小的儿童中的变异性进行深入分析。
