Does the Environment Have an Enduring Effect on ADHD? A Longitudinal Study of Monozygotic Twin Differences in Children
2016 (English)In: Journal of Abnormal Child Psychology, ISSN 0091-0627, E-ISSN 1573-2835, Vol. 44, no 8, 1487-1501 p.Article in journal (Refereed) Published
Environmental factors play a key role in the development of Attention-Deficit/Hyperactivity Disorder (ADHD), but the long-term effects of these factors are still unclear. This study analyses data from 1024 monozygotic (identical) twins in Australia, the United States, and Scandinavia who were assessed for ADHD in Preschool, Kindergarten, Grade 1, and Grade 2. Differences within each twin pair were used as a direct measure of non-shared environmental effects. The Trait-State-Occasion (TSO) model developed by Cole et al. (Psychological Methods, 10, 3-20, 2005) was used to separate the non-shared environmental effects into stable factors, and transient factors that excluded measurement error. Stable factors explained, on average, 44 % and 39 % of the environmental variance in hyperactive-impulsive and inattentive symptoms, respectively. Transient effects explained the remaining 56 % and 60 % of variance. The proportion of stable variance was higher than expected based on previous research, suggesting promise for targeted interventions if future research identifies these stable risk factors.
Place, publisher, year, edition, pages
SPRINGER/PLENUM PUBLISHERS , 2016. Vol. 44, no 8, 1487-1501 p.
ADHD; Environment; Genetics; Longitudinal; Twins
Psychology (excluding Applied Psychology)
IdentifiersURN: urn:nbn:se:liu:diva-132654DOI: 10.1007/s10802-016-0145-9ISI: 000386116700004PubMedID: 26993487OAI: oai:DiVA.org:liu-132654DiVA: diva2:1048384
Funding Agencies|Australian Research Council [A79906201, DP0770805, DP0663498]; National Institutes of Health [2 P50 HD27802, 1 R01 HD38526]; Research Council of Norway [154715/330]; Swedish Research Council [345-2002-3701]; University of Stavanger2016-11-212016-11-182016-11-21