Anne B Arnett1, Bruce F Pennington2, Robin L Peterson3,4, Erik G Willcutt5, John C DeFries5, Richard K Olson5. 1. Department of Psychiatry & Behavioral Sciences, University of Washington, Seattle, WA, USA. 2. Department of Clinical Child Psychology, University of Denver, Denver, CO, USA. 3. Colorado Rehabilitation & Therapy, Children's Hospital, Denver, CO, USA. 4. Department of Psychology, University of Colorado School of Medicine, Aurora, CO, USA. 5. Institute for Behavioral Genetics, University of Colorado at Boulder, Boulder, CO, USA.
Abstract
BACKGROUND: Males are diagnosed with dyslexia more frequently than females, even in epidemiological samples. This may be explained by greater variance in males' reading performance. METHODS: We expand on previous research by rigorously testing the variance difference theory, and testing for mediation of the sex difference by cognitive correlates. We developed an analytic framework that can be applied to group differences in any psychiatric disorder. RESULTS: Males' overrepresentation in the low performance tail of the reading distribution was accounted for by mean and variance differences across sex. There was no sex difference at the high performance tail. Processing speed (PS) and inhibitory control partially mediated the sex difference. Verbal reasoning emerged as a strength in males. CONCLUSIONS: Our results complement a previous finding that PS partially mediates the sex difference in symptoms of attention deficit/hyperactivity disorder (ADHD), and helps explain the sex difference in both dyslexia and ADHD and their comorbidity.
BACKGROUND: Males are diagnosed with dyslexia more frequently than females, even in epidemiological samples. This may be explained by greater variance in males' reading performance. METHODS: We expand on previous research by rigorously testing the variance difference theory, and testing for mediation of the sex difference by cognitive correlates. We developed an analytic framework that can be applied to group differences in any psychiatric disorder. RESULTS: Males' overrepresentation in the low performance tail of the reading distribution was accounted for by mean and variance differences across sex. There was no sex difference at the high performance tail. Processing speed (PS) and inhibitory control partially mediated the sex difference. Verbal reasoning emerged as a strength in males. CONCLUSIONS: Our results complement a previous finding that PS partially mediates the sex difference in symptoms of attention deficit/hyperactivity disorder (ADHD), and helps explain the sex difference in both dyslexia and ADHD and their comorbidity.
Authors: J S Perrin; G Leonard; M Perron; G B Pike; A Pitiot; L Richer; S Veillette; Z Pausova; T Paus Journal: Neuroimage Date: 2009-01-24 Impact factor: 6.556
Authors: Stuart J Ritchie; Simon R Cox; Xueyi Shen; Michael V Lombardo; Lianne M Reus; Clara Alloza; Mathew A Harris; Helen L Alderson; Stuart Hunter; Emma Neilson; David C M Liewald; Bonnie Auyeung; Heather C Whalley; Stephen M Lawrie; Catharine R Gale; Mark E Bastin; Andrew M McIntosh; Ian J Deary Journal: Cereb Cortex Date: 2018-08-01 Impact factor: 5.357