Coventry, William

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Given Name
William
William
Surname
Coventry
UNE Researcher ID
une-id:wcovent2
Email
wcovent2@une.edu.au
URI
Preferred Given Name
William
School/Department
School of Psychology

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Now showing 1 - 10 of 16
  • Thumbnail Image
    Publication
    Identical Genes, Unique Environments: A Qualitative Exploration of Persistent Monozygotic-Twin Discordance in Literacy and Numeracy
    (Frontiers Research Foundation, 2019-03-21)
    Larsen, Sally 
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    Byrne, Brian J 
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    Little, Callie 
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    Coventry, William 
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    Ho, Connie S
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    Olson, Richard K
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    Stevenson, Annette C 
    This study aimed to explore unique environmental factors impacting differential academic trajectories among Australian school students. Monozygotic (MZ) twin pairs who were consistently discordant in results of nationwide standardized tests of reading, numeracy or writing between Grades 3 and 9 were identified. MZ twins control for genes, gender, age, and aspects of the home and school environment shared by twins. Thus, any difference between MZ twins in academic outcomes can be attributed to the unique environment experienced by each twin. From 551 MZ twin pairs with three or four sets of test results, we identified 55 pairs who were substantially and consistently discordant in reading, numeracy or writing between Grades 3 and 9. Parents were contacted for interview, resulting in 40 semi-structured interviews. Qualitative data analysis revealed three major themes, interpreted by parents as possible contributors to persistent academic discordance: biological mechanisms, school-based factors, and personal factors. We discuss implications for educational practice, policy, and research.
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    Differential Influences of Genes and Environment Across the Distribution of Reading Ability
    (Springer New York LLC, 2019-08-05)
    McGowan, Dipti
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    Little, Callie W 
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    Coventry, William L 
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    Corley, Robin
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    Olson, Richard K
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    Samuelsson, Stefan
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    Byrne, Brian 
    We partitioned early childhood reading into genetic and environmental sources of variance and examined the full distribution of ability levels from low through normal to high as computed by quantile regression. The full sample comprised twin pairs measured at preschool (n = 977), kindergarten (n = 1028), grade 1 (n = 999), and grade 2 (n = 1000). Quantile regression analyses of the full distribution of literacy ability showed genetic influence in all grades from preschool to grade 2. At preschool, the low end of the distribution had higher genetic influence than the high end of the distribution and the shared environment influence was the opposite. These shared environment influences of preschool became insignificant with formal schooling. This suggests that higher scores in pre-literacy skills (preschool) are more influenced by shared environment factors, though these are short-lived. This study discusses the factors that may be influencing the results.
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    Publication
    Multivariate Genetic Analysis of Learning and Early Reading Development
    (Routledge, 2013)
    Byrne, Brian J 
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    Wadsworth, Sally
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    Boehme, Kristi
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    Talk, Andrew 
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    Coventry, William L 
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    Olson, Richard K
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    Samuelsson, Stefan
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    Corley, Robin
    The genetic factor structure of a range of learning measures was explored in twin children, recruited in preschool and followed to Grade 2 (N = 2,084). Measures of orthographic learning and word reading were included in the analyses to determine how these patterned with the learning processes. An exploratory factor analysis of the genetic correlations among the variables indicated a three-factor model. Vocabulary tests loaded on the first factor, the Grade 2 measures of word reading and orthographic learning, plus preschool letter knowledge, loaded on the second, and the third was characterized by tests of verbal short-term memory. The three genetic factors correlated, with the second (print) factor showing the most specificity. We conclude that genetically influenced learning processes underlying print-speech integration, foreshadowed by preschool letter knowledge, have a degree of independence from genetic factors affecting spoken language. We also argue that the psychology and genetics of associative learning be afforded a more central place in studies of reading (dis)ability and suggest some links to molecular studies of the genetics of learning.
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    Publication
    Genetic and Environmental Influences on Literacy and Numeracy Performance in Australian School Children in Grades 3, 5, 7, and 9
    (Springer New York LLC, 2016)
    Grasby, Katrina
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    Coventry, William L 
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    Byrne, Brian J 
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    Olson, Richard K
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    Medland, Sarah E
    We examined the extent to which genes and the environment contributed to variation in and covariation among reading, spelling, grammar and punctuation, writing, and numeracy in Australian school children in Grades 3, 5, 7, and 9. Heritability was generally high: reading .58-.71 (excepting Grade 5 girls), spelling .68-.78; grammar and punctuation .52-.66, writing .39-.52, and numeracy .39-.79. Boys' performance varied more than girls in spelling and numeracy, and the common environment was a greater influence in girls than boys in Grade 3 numeracy and Grade 5 reading. Independent pathway models showed similar genetic and environmental structures at each grade with approximately one third to one half of the variation in each domain due to genes that influenced all domains. The covariation among the domains was largely mediated by genes. Results suggest substantial uniformity in the environmental factors influencing these academic domains.
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    The Academic Development Study of Australian Twins (ADSAT): Research Aims and Design
    (Cambridge University Press, 2020-06-02)
    Larsen, Sally A 
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    Little, Callie W 
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    Grasby, Katrina
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    Byrne, Brian 
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    Olson, Richard K
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    Coventry, William L 
    The Academic Development Study of Australian Twins was established in 2012 with the purpose of investigating the relative influence of genes and environments in literacy and numeracy capabilities across two primary and two secondary school grades in Australia. It is the first longitudinal twin project of its kind in Australia and comprises a sample of 2762 twin pairs, 40 triplet sets and 1485 nontwin siblings. Measures include standardized literacy and numeracy test data collected at Grades 3, 5, 7 and 9 as part of the National Assessment Program: Literacy and Numeracy. A range of demographic and behavioral data was also collected, some at multiple longitudinal time points. This article outlines the background and rationale for the study and provides an overview for the research design, sample and measures collected. Findings emerging from the project and future directions are discussed.
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    Gene-Environment Interactions in ADHD: The Roles of SES and Chaos
    (Springer New York LLC, 2018)
    Gould, Karen
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    Coventry, William L 
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    Olson, Richard K
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    Byrne, Brian J 
    Although attention-deficit/hyperactivity disorder (ADHD) is highly heritable, emerging evidence suggests symptoms are associated with interactions between genes and the environment (GxE) during development. This study tested whether heritability of ADHD symptoms is moderated by two environmental factors: socioeconomic status (SES) and chaos (household disorganisation). A population sample of 520 twin pairs (N = 1040, 52.3% female) from 6 to 15 years completed measures of behavior and home environment. Structural equation modelling was then used to test whether environmental factors were associated with a change in the extent to which genes explain variability in ADHD symptoms. Neither chaos nor SES moderated heritability, with consistent contributions from both genes and environment indicated across socioeconomic strata and levels of chaos. This finding contrasts with those of previous research, underlining the need to replicate results in the emerging field of GxE research across different populations and statistical methods. Robust findings may assist in developing targeted interventions for genetically vulnerable individuals.
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    Publication
    Genetic and Environmental Influences on Inattention, Hyperactivity-Impulsivity, and Reading: Kindergarten to Grade 2
    (Routledge, 2010)
    Ebejer, Jane 
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    Coventry, William L 
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    Byrne, Brian J 
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    Willcutt, Erik G
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    Olson, Richard K
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    Corley, Robin
    Twin children from Australia, Scandinavia, and the United States were assessed for inattention, hyperactivity-impulsivity, and reading across the first 3 school years. Univariate behavior-genetic analyses indicated substantial heritability for all three variables in all years. Longitudinal analyses showed one genetic source operating across the time span and a second entering in the second school year for each variable, though possibly not reliable for inattention. Other analyses confirmed previous findings of pleiotropy (shared genes) between inattention and reading and showed that this genetic overlap is in place from kindergarten onwards and is restricted to one of the genetic sources that affect reading and inattention. The results extend previous conclusions about the developmental trajectories of inattention, hyperactivity-impulsivity, and reading and their relationships. Limitations of this study are discussed, as are educational implications.
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    Estimating classroom-level influences on literacy and numeracy: A twin study
    (American Psychological Association, 2020-08)
    Grasby, Katrina L
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    Little, Callie W 
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    Byrne, Brian 
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    Coventry, William L 
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    Olson, Richard K
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    Larsen, Sally 
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    Samuelsson, Stefan
    Classroom-level influences on literacy skills in kindergarten through Grade 2, and on literacy and numeracy skills in Grades 3, 5, 7, and 9, were examined by comparing the similarity of twins who shared or did not share classrooms with each other. We analyzed two samples using structural equation modeling adapted for twin data. The first, Study 1, was of Australia-wide tests of literacy and numeracy, with 1,098; 1,080; 790, and 812 complete twin pairs contributing data for Grades 3, 5, 7, and 9, respectively. The second, Study 2, was of literacy tests from 753 twin pairs from kindergarten through Grade 2, which included a sample of United States and Australian students and was a reanalysis and extension of Byrne et al. (2010). Classroom effects were mostly nonsignificant; they accounted for only 2–3% of variance in achievement when averaged over tests and grades. Although the averaged effects may represent a lower-bound figure for classroom effects, and the design cannot detect classroom influences limited to individual students, the results are at odds with claims in public discourse of substantial classroom-level influences, which are mostly portrayed as teacher effects.
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    Publication
    Associations between selected dietary behaviours and academic achievement: A study of Australian school aged children
    (Elsevier BV, 2017-09-01)
    Burrows, Tracy
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    Goldman, Sharni
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    Olson, Richard K
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    Byrne, Brian 
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    Coventry, William L 

    Background: Research investigating the effects of dietary behaviours on children's academic achievement has predominately focused on breakfast consumption. The aim of this study was to conduct secondary analysis to examine associations between a range of dietary behaviours and children's academic achievement.

    Methodology: Data on five dietary variables (fruit intake; vegetable intake; consumption of takeaway; sugar sweetened beverages; and breakfast) and scores in the five domains of a standardised academic achievement test known as NAPLAN (reading, writing, grammar/punctuation, spelling and numeracy) were obtained for Australian children aged 8–15 years in school grades three (n = 1185), five (n = 1147), seven (n = 1053) and nine (n = 860). Mixed linear models adjusted for socioeconomic status and gender were used to examine associations between dietary behaviours and academic scores.

    Results: Greater consumption of vegetables with the evening meal (7 nights/week) was associated with higher test scores in the domains of spelling and writing (p=<0.01), with the greatest effect observed for spelling with a mean score difference of 86 ± 26.5 NAPLAN points between the highest and lowest levels of consumption (95% CI: 34.0–138.1; p=<0.01). Increased consumption of sugar sweetened beverages was associated with significantly lower test scores in reading, writing, grammar/punctuation and numeracy (<0.01).

    Principle conclusions: The findings of this study demonstrate dietary behaviours are associated with higher academic achievement. Future research should further explore relationships between a wide range of dietary behaviours and children's academic achievement.

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    Publication
    Does the Environment Have an Enduring Effect on ADHD?: A Longitudinal Study of Monozygotic Twin Differences in Children
    (Springer New York LLC, 2016)
    Livingstone, Luisa T
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    Coventry, William L 
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    Corley, Robin P
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    Willcutt, Erik G
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    Samuelsson, Stefan
    ;
    Olson, Richard K
    ;
    Byrne, Brian J 
    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.