title: Visual perceptual difficulties and under-achievement at school in a large community-based sample of children.
abstract: BACKGROUND
  Difficulties with visual perception (VP) are often described in children with neurological or developmental problems. However, there are few data regarding the range of visual perceptual abilities in populations of normal children, or on the impact of these abilities on children's day-to-day functioning.
  
  
  METHODS
  Data were obtained for 4512 participants in an ongoing birth cohort study (Avon Longitudinal Study of Parents and Children; ALSPAC). The children's mothers responded to questions designed to elicit indications of visual perceptual difficulties or immaturity, when their children were aged 13 years. We examined associations with standardised school test results in reading and in mathematics at age 13-14 years (SATS-KS3), accounting for potential confounders including IQ.
  
  
  RESULTS
  Three underlying factors explained half the variance in the VP question responses. These correlated best with questions on interpreting cluttered scenes; guidance of movement and face recognition. The adjusted parameter estimates (95% CI) for the cluttered-scenes factor (0.05; 0.02 to 0.08; p<0.001) suggested positive associations with the reading test results whilst that for the guidance-of-movement factor (0.03; 0.00 to 0.06; p = 0.026) suggested positive association with the mathematics results. The raw scores were associated with both test results.
  
  
  CONCLUSIONS
  VP abilities were widely distributed in this sample of 13-year old children. Lower levels of VP function were associated with under-achievement in reading and in mathematics. Simple interventions can help children with VP difficulties, so research is needed into practicable, cost-effective strategies for identification and assessment, so that support can be targeted appropriately.
authors: School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom. Cathy.Williams@bristol.ac.uk
authors: Cathy
authors: C
authors: Williams
authors: Kate
authors: K
authors: Northstone
authors: Ricardo
authors: R
authors: Sabates
authors: Leon
authors: L
authors: Feinstein
authors: Alan
authors: A
authors: Emond
authors: Gordon N
authors: GN
authors: Dutton
mesh_terms: D000293:Adolescent; D006801:Humans; D025341:Principal Component Analysis; D014796:Visual Perception