title: Chaotic homes and school achievement: a twin study.
abstract: BACKGROUND
  Chaotic homes predict poor school performance. Given that it is known that genes affect both children's experience of household chaos and their school achievement, to what extent is the relationship between high levels of noise and environmental confusion in the home, and children's school performance, mediated by heritable child effects? This is the first study to explore the genetic and environmental pathways between household chaos and academic performance.
  
  
  METHODS
  Children's perceptions of family chaos at ages 9 and 12 and their school performance at age 12 were assessed in more than 2,300 twin pairs. The use of child-specific measures in a multivariate genetic analysis made it possible to investigate the genetic and environmental origins of the covariation between children's experience of chaos in the home and their school achievement.
  
  
  RESULTS
  Children's experience of family chaos and their school achievement were significantly correlated in the expected negative direction (r = -.26). As expected, shared environmental factors explained a large proportion (63%) of the association. However, genetic factors accounted for a significant proportion (37%) of the association between children's experience of household chaos and their school performance.
  
  
  CONCLUSIONS
  The association between chaotic homes and poor performance in school, previously assumed to be entirely environmental in origin, is in fact partly genetic. How children's home environment affects their academic achievement is not simply in the direction environment → child → outcome. Instead, genetic factors that influence children's experience of the disordered home environment also affect how well they do at school. The relationship between the child, their environment and their performance at school is complex: both genetic and environmental factors play a role.
authors.affiliation: King's College London, MRC Social, Genetic & Developmental Psychiatry Centre, Institute of Psychiatry, London, UK. ken.hanscombe@kcl.ac.uk
authors.forename: Ken B
authors.initials: KB
authors.lastname: Hanscombe
authors.forename: Claire M A
authors.initials: CM
authors.lastname: Haworth
authors.forename: Oliver S P
authors.initials: OS
authors.lastname: Davis
authors.forename: Sara R
authors.initials: SR
authors.lastname: Jaffee
authors.forename: Robert
authors.initials: R
authors.lastname: Plomin
mesh_terms: D000124:Achievement; D000704:Analysis of Variance; D002648:Child; D004522:Educational Status; D004777:Environment; D005260:Female; D006801:Humans; D008297:Male; D009622:Noise; D010287:Parent-Child Relations; D016487:Parenting / Q000523:psychology*; D012931:Social Environment; D012938:Social Perception