Klein Christoph, Wendling Katharina, Huettner Paul, Ruder Hans, Peper Martin
School of Psychology, University of Wales, Penrallt Road, Bangor, Gwynedd, Wales, UK.
Biol Psychiatry. 2006 Nov 15;60(10):1088-97. doi: 10.1016/j.biopsych.2006.04.003. Epub 2006 Jun 27.
This study is based on a comprehensive survey of the neuropsychological attention-deficit hyperactivity disorder (ADHD) literature and presents the first psychometric analyses of different parameters of intra-subject variability (ISV) in patients with ADHD compared to healthy controls, using the Continuous Performance Test, a Go-NoGo task, a Stop Signal Task, as well as N-back tasks.
Data of 57 patients with ADHD and 53 age- and gender-matched controls were available for statistical analysis. Different parameters were used to describe central tendency (arithmetic mean, median), dispersion (standard deviation, coefficient of variation, consecutive variance), and shape (skewness, excess) of reaction time distributions, as well as errors (commissions and omissions).
Group comparisons revealed by far the strongest effect sizes for measures of dispersion, followed by measures of central tendency, and by commission errors. Statistical control of ISV reduced group differences in the other measures substantially. One (patients) or two (controls) principal components explained up to 67% of the inter-individual differences in intra-individual variability.
Results suggest that, across a variety of neuropsychological tests, measures of ISV contribute best to group discrimination, with limited incremental validity of measures of central tendency and errors. Furthermore, increased ISV might be a unitary construct in ADHD.
本研究基于对注意力缺陷多动障碍（ADHD）神经心理学文献的全面调查，并首次对ADHD患者与健康对照者的个体内变异性（ISV）不同参数进行了心理测量分析，采用了连续性能测试、Go-NoGo任务、停止信号任务以及N-back任务。
57例ADHD患者和53例年龄及性别匹配的对照者的数据可用于统计分析。使用不同参数来描述反应时间分布的集中趋势（算术平均数、中位数）、离散度（标准差、变异系数、连续方差）和形状（偏度、峰度），以及错误（错误操作和遗漏）。
组间比较显示，离散度测量的效应量迄今为止最为显著，其次是集中趋势测量，以及错误操作。对ISV进行统计控制后，其他测量中的组间差异大幅减小。一个（患者组）或两个（对照组）主成分解释了个体内变异性个体间差异的67%。
结果表明，在各种神经心理学测试中，ISV测量对组间区分的贡献最大，集中趋势测量和错误测量的增量效度有限。此外，ADHD中ISV增加可能是一个单一结构。
