title: Unintentional injuries in a twin study of preschool children: environmental, not genetic, risk factors.
abstract: OBJECTIVE
  To analyze the relative contribution of latent genetic and environmental factors to differences in the injury liability of children, and to examine the association between measured socio-economic, family, and child-behavior variables and unintentional injury risk.
  
  
  METHODS
  Unintentional injuries from birth to age 5, together with information regarding measured risk variables, were reported by mothers in a sample of 1027 same-sex twin pairs from a nationally representative 1994-1995 birth cohort.
  
  
  RESULTS
  Child-specific environmental factors accounted for most of the variance (86.4%) in the likelihood of ever having an injury. When considering the risk of two or more injuries child-specific environmental factors explained 60.2% of the variance and family-wide environmental influence 39.8%. Measured socio-economic, family, and child-behavior factors predicted frequent injury.
  
  
  CONCLUSIONS
  Results give little support to the concept of a heritable injury-prone trait in preschool children; environmental influences accounted for most of the injury variance in this sample. However, behavioral variables, especially the child's externalizing problem behaviors, are also important in explaining unintentional injuries.
authors.affiliation: Area of Psychobiology, Department of Human Anatomy and Psychobiology, Murcia University, 30100 Espinardo-Murcia, Spain. ordonana@um.es
authors.forename: Juan R
authors.initials: JR
authors.lastname: Ordoñana
authors.forename: Avshalom
authors.initials: A
authors.lastname: Caspi
authors.forename: Terrie E
authors.initials: TE
authors.lastname: Moffitt
mesh_terms: D000059:Accidents; D002675:Child, Preschool; D004777:Environment; D005260:Female; D006801:Humans; D008297:Male; D015995:Prevalence; D012307:Risk Factors; D014427:Twins; D014947:Wounds and Injuries / Q000453:epidemiology*