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- Arnett, Anett, et al.
(författare)
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The SWAN captures variance at the negative and positive ends of the ADHD Symptom dimension
- 2013
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Ingår i: Journal of Attention Disorders. - : Sage Publications. - 1087-0547 .- 1557-1246. ; 17:2, s. 152-162
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Tidskriftsartikel (refereegranskat)abstract
- Objective: The Strengths and Weaknesses of ADHD Symptoms and Normal Behavior (SWAN) Rating Scale differs from previous parent reports of ADHD in that it was designed to also measure variability at the positive end of the symptom spectrum. Method: The psychometric properties of the SWAN were tested and compared with an established measure of ADHD, the Disruptive Behavior Rating Scale (DBRS). Results: The SWAN demonstrates comparable validity, reliability, and heritability to the DBRS. Furthermore, plots of the SWAN and DBRS reveal heteroscedasticity, which supports the SWAN as a preferred measure of positive attention and impulse regulation behaviors. Conclusion: The ability of the SWAN to measure additional variance at the adaptive end of the ADHD symptom dimensions makes it a promising tool for behavioral genetic studies of ADHD.
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| 2. |
- Byrne, Brian, et al.
(författare)
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Genetic and environmental influences on early literacy
- 2006
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Ingår i: Journal of research in reading (Print). - : Wiley. - 0141-0423 .- 1467-9817. ; 29:1, s. 33-49
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Tidskriftsartikel (refereegranskat)abstract
- Prereading and early reading skills of preschool twin children in Australia, Scandinavia and the United States were explored in a genetically sensitive design (max. N = 627 preschool pairs and 422 kindergarten pairs). Analyses indicated a strong genetic influence on preschool phonological awareness, rapid naming and verbal memory. Print awareness, vocabulary and grammar/morphology were subject primarily to shared environment effects. There were significant genetic and shared environment correlations among the preschool traits. Kindergarten reading, phonological awareness and rapid naming were primarily affected by genes, and spelling was equally affected by genes and shared environment. Multivariate analyses revealed genetic and environmental overlap and independence among kindergarten variables. Longitudinal analyses showed genetic continuity as well as change in phonological awareness and rapid naming across the 2 years. Relations among the preschool variables of print awareness, phonological awareness and rapid naming and kindergarten reading were also explored in longitudinal analyses. Educational implications are discussed. © United Kingdom Literacy Association 2006.
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| 3. |
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| 4. |
- Byrne, Brian, et al.
(författare)
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Longitudinal twin study of early literacy development : Preschool through Grade 1
- 2007
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Ingår i: Reading and writing. - : Springer Science and Business Media LLC. - 0922-4777 .- 1573-0905. ; 20:1-2, s. 77-102
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Tidskriftsartikel (refereegranskat)abstract
- Grade 1 literacy skills of twin children in Australia (New South Wales) and the United States (Colorado) were explored in a genetically sensitive design (N = 319 pairs). Analyses indicated strong genetic influence on word and nonword identification, reading comprehension, and spelling. Rapid naming showed more modest, though reliable, genetic influence. Phonological awareness was subject to high nonshared environment and no reliable genetic effects, and individual measures of memory and learning were also less affected by genes than nonshared environment. Multivariate analyses showed that the same genes affected word identification, reading comprehension, and spelling. Country comparisons indicated that the patterns of genetic influence on reading and spelling in Grade 1 were similar, though for the U.S. but not the Australian children new genes came on stream in the move from kindergarten to Grade 1. We suggest that this is because the more intensive kindergarten literacy curriculum in New South Wales compared with Colorado, consistent with the mean differences between the two countries, means that more of the genes are "online" sooner in Australia because of accelerated overall reading development. © Springer Science+Business Media B.V. 2007.
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| 7. |
- Christopher, Micaela, et al.
(författare)
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The genetic and environmental etiologies of individual differences in early reading growth in Australia, the United States and Scandinavia
- 2013
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Ingår i: Journal of experimental child psychology (Print). - : Elsevier. - 0022-0965 .- 1096-0457. ; 115:3, s. 453-467
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Tidskriftsartikel (refereegranskat)abstract
- This first cross-country twin study of individual differences in reading growth from post-kindergarten to post-second grade analyzed data from 487 twin pairs from the United States, 267 twin pairs from Australia, and 280 twin pairs from Scandinavia. Data from two reading measures were fit to biometric latent growth models. Individual differences for the reading measures at post-kindergarten in the United States and Australia were due primarily to genetic influences and to both genetic and shared environmental influences in Scandinavia. In contrast, individual differences in growth generally had large genetic influences in all countries. These results suggest that genetic influences are largely responsible for individual differences in early reading development. In addition, the timing of the start of formal literacy instruction may affect the etiology of individual differences in early reading development but have only limited influence on the etiology of individual differences in growth.
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| 8. |
- L Coventry, William, et al.
(författare)
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Does Classroom Separation Affect Twins Reading Ability in the Early Years of School?
- 2009
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Ingår i: TWIN RESEARCH AND HUMAN GENETICS. - : Cambridge University Press (CUP). - 1832-4274 .- 1839-2628. ; 12:5, s. 455-461
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Tidskriftsartikel (refereegranskat)abstract
- In this article we report on reading ability of twin children in kindergarten to Grade 2 as a function of whether members of the pairs are assigned to the same or different classrooms. All analyses were run using mixed model regressions to account for the interdependence between twin pairs. The samples, total N = 1505, are from Australia and the United States. We found a close-to-significant difference in favor of same-class children in kindergarten and Grade 1. However, when results were adjusted to take account of pre-existing differences in disruptive behavior and in preliteracy ability, the class assignment effects disappeared. We suggest that these pre-existing differences, particularly disruptive behavior, are influencing decisions about whether to separate twins or not and also affecting early reading performance, a conclusion supported by significant correlations between the behavioral measures, preliteracy, and school-based reading. We conclude that, on average, early literacy in twins is not directly affected by their assignment to the same or different classrooms.
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| 10. |
- Pennington, Bruce, et al.
(författare)
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Individual prediction of dyslexia by single vs. multiple deficit models.
- 2012
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Ingår i: Journal of Abnormal Psychology. - : American Psychological Association. - 0021-843X .- 1939-1846. ; 121:1, s. 212-224
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Tidskriftsartikel (refereegranskat)abstract
- The overall goals of this study were to test single versus multiple cognitive deficit models of dyslexia (reading disability) at the level of individual cases and to determine the clinical utility of these models for prediction and diagnosis of dyslexia. To accomplish these goals, we tested five cognitive models of dyslexia-two single-deficit models, two multiple-deficit models, and one hybrid model-in two large population-based samples, one cross-sectional (Colorado Learning Disability Research Center) and one longitudinal (International longitudinal Twin Study). The cognitive deficits included in these cognitive models were in phonological awareness, language skill, and processing speed and/or naming speed. To determine whether an individual case fit one of these models, we used two methods: 1) the presence or absence of the predicted cognitive deficits, and 2) whether the individuals level of reading skill best fit the regression equation with the relevant cognitive predictors (i.e., whether their reading skill was proportional to those cognitive predictors.) We found that roughly equal proportions of cases met both tests of model fit for the multiple deficit models (30-36%) and single deficit models (24-28%); hence, the hybrid model provided the best overall fit to the data. The remaining roughly 40% of cases in each sample lacked the deficit or deficits that corresponded with their best-fitting regression model. We discuss the clinical implications of these results for both diagnosis of school-age children and preschool prediction of children at risk for dyslexia.
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