title: Impaired balance in developmental dyslexia? A meta-analysis of the contending evidence.
abstract: BACKGROUND
  Developmental dyslexia is typically defined by deficits in phonological skills, but it is also associated with anomalous performance on measures of balance. Although balance assessments are included in several screening batteries for dyslexia, the association between impairments in literacy and deficits in postural stability could be due to the high co-occurrence of dyslexia with other developmental disorders in which impairments of motor behaviour are also prevalent.
  
  
  METHODS
  We identified 17 published studies that compared balance function between dyslexia and control samples and obtained effect-sizes for each. Contrast and association analyses were used to quantify the influence of hypothesised moderator variables on differences in effects across studies.
  
  
  RESULTS
  The mean effect-size of the balance deficit in dyslexia was .64 (95% CI = .44-.78) with heterogeneous findings across the population of studies. Probable co-occurrence of other developmental disorders and variability in intelligence scores in the dyslexia samples were the strongest moderator variables of effect-size.
  
  
  CONCLUSIONS
  Balance deficits are associated with dyslexia, but these effects are apparently more strongly related to third variables other than to reading ability. Deficits of balance may indicate increased risk of developmental disorder, but are unlikely to be uniquely associated with dyslexia.
authors.affiliation: School of Life and Health Sciences, Psychology, Aston University, Birmingham, UK.
authors.forename: Kim S H
authors.initials: KS
authors.lastname: Rochelle
authors.forename: Joel B
authors.initials: JB
authors.lastname: Talcott
mesh_terms: D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis / Q000523:psychology; D002648:Child; D015897:Comorbidity; D004410:Dyslexia / Q000175:diagnosis* / Q000523:psychology; D006801:Humans; D007360:Intelligence; D019957:Motor Skills Disorders / Q000175:diagnosis / Q000523:psychology; D004856:Postural Balance