Ebejer, Jane; Medland, Sarah; Van Der Werf, Julius H; Wright, M J; Henders, A K; Gillespie, N A; Hickie, I B; Martin, Nicholas; Duffy, D L

Author(s)

Ebejer, Jane

Medland, Sarah

Van Der Werf, Julius H

Wright, M J

Henders, A K

Gillespie, N A

Hickie, I B

Martin, Nicholas

Duffy, D L

Publication Date

2015

Abstract

The heritability of attention-deficit/hyperactivity disorder (ADHD) is higher for children than adults. This may be due to increasing importance of environment in symptom variation, measurement inaccuracy when two raters report behavior of a twin-pair, a contrast effect resulting from parental comparison of siblings and/or dimensionality of measures. We examine rater contrast and sex effects in ADHD subtypes using a dimensional scale and compare the aetiology of self, versus maternal-report. Data were collected using the Strengths and Weaknesses of ADHD and Normal Behaviour Scale (SWAN): maternal-report for 3,223 twins and siblings (mean age 21.2, SD = 6.3) and self-report for 1,617 twins and siblings (mean age 25.5, SD = 3.2). Contrast effects and magnitude of genetic and environmental contributions to variance of ADHD phenotypes (inattention, hyperactivity-impulsivity, combined behaviours) were examined using structural equation modeling. Contrast effects were evident for maternal-report hyperactivity-impulsivity (b = −0.04) and self-report inattention (−0.09) and combined ADHD (−0.08). Dominant genetic effects were shared by raters for inattention, hyperactivity-impulsivity and combined ADHD. Broad-sense heritability was equal across sex for maternal-report inattention, hyperactivity-impulsivity and combined ADHD (0.72, 0.83, 0.80). Heritability for corresponding subtypes in self-reported data were best represented by sex (0.46, 0.30, 0.39 for males; 0.69, 0.41, 0.65 for females). Heritability difference between maternal and self-report ADHD was due to greater variance of male specific environment in self-report data. Self-reported ADHD differed across sex by magnitude of specific environment and genetic effects.

Citation

Behavior Genetics, 45(1), p. 35-50

ISSN

1573-3297

0001-8244

Link

https://hdl.handle.net/1959.11/17726

Publisher

Springer New York LLC

Title

Contrast Effects and Sex Influence Maternal and Self-Report Dimensional Measures of Attention-Deficit Hyperactivity Disorder

Type of document

Journal Article

Entity Type

Publication

Author(s)	Ebejer, Jane Medland, Sarah Van Der Werf, Julius H Wright, M J Henders, A K Gillespie, N A Hickie, I B Martin, Nicholas Duffy, D L
Publication Date	2015
Abstract	The heritability of attention-deficit/hyperactivity disorder (ADHD) is higher for children than adults. This may be due to increasing importance of environment in symptom variation, measurement inaccuracy when two raters report behavior of a twin-pair, a contrast effect resulting from parental comparison of siblings and/or dimensionality of measures. We examine rater contrast and sex effects in ADHD subtypes using a dimensional scale and compare the aetiology of self, versus maternal-report. Data were collected using the Strengths and Weaknesses of ADHD and Normal Behaviour Scale (SWAN): maternal-report for 3,223 twins and siblings (mean age 21.2, SD = 6.3) and self-report for 1,617 twins and siblings (mean age 25.5, SD = 3.2). Contrast effects and magnitude of genetic and environmental contributions to variance of ADHD phenotypes (inattention, hyperactivity-impulsivity, combined behaviours) were examined using structural equation modeling. Contrast effects were evident for maternal-report hyperactivity-impulsivity (b = −0.04) and self-report inattention (−0.09) and combined ADHD (−0.08). Dominant genetic effects were shared by raters for inattention, hyperactivity-impulsivity and combined ADHD. Broad-sense heritability was equal across sex for maternal-report inattention, hyperactivity-impulsivity and combined ADHD (0.72, 0.83, 0.80). Heritability for corresponding subtypes in self-reported data were best represented by sex (0.46, 0.30, 0.39 for males; 0.69, 0.41, 0.65 for females). Heritability difference between maternal and self-report ADHD was due to greater variance of male specific environment in self-report data. Self-reported ADHD differed across sex by magnitude of specific environment and genetic effects.
Citation	Behavior Genetics, 45(1), p. 35-50
ISSN	1573-3297 0001-8244
Link	https://hdl.handle.net/1959.11/17726
Publisher	Springer New York LLC
Title	Contrast Effects and Sex Influence Maternal and Self-Report Dimensional Measures of Attention-Deficit Hyperactivity Disorder
Type of document	Journal Article
Entity Type	Publication

Contrast Effects and Sex Influence Maternal and Self-Report Dimensional Measures of Attention-Deficit Hyperactivity Disorder

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