title: [Is a specific disorder of arithmetic skills as common as reading/spelling disorder?].
abstract: BACKGROUND
  Referring to the prevalence rates of learning disorders in the research literature, the numbers of mathematics disorder and reading/spelling disorder are often reported to be identical. However, the correlation between intelligence level and reading/spelling skills is much weaker than between intelligence and arithmetic skills. If the same definition criterion is applied to both disorders, a lower prevalence rate for mathematics disorder should be expected.
  
  
  OBJECTIVE
  Are there differences in the prevalence estimates for learning disorders depending on the definition criterion?
  
  
  METHODS
  A large representative sample of German students (N=1970) was used to review the hypothesis.
  
  
  RESULTS
  Depending on the definition criterion, we could show a prevalence range of mathematics disorder between 0.1% and 8.1% in the same sample. Using the same definition criterion for both learning disorders, there are two to three times as many students with reading/spelling disorder than those with mathematics disorder.
  
  
  CONCLUSIONS
  Whenever children with reading/spelling disorder are compared to children with mathematics disorder, the same definition criterion has to be applied.
authors.affiliation: Lehrstuhl für Klinische Psychologie/Psychotherapie, Universität Potsdam, Potsdam-Golm. awysch@uni-potsdam.de
authors.forename: Anne
authors.initials: A
authors.lastname: Wyschkon
authors.forename: Juliane
authors.initials: J
authors.lastname: Kohn
authors.forename: Katja
authors.initials: K
authors.lastname: Ballaschk
authors.forename: Günter
authors.initials: G
authors.lastname: Esser
mesh_terms: D002648:Child; D003430:Cross-Sectional Studies; D002658:Developmental Disabilities / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology; D004410:Dyslexia / Q000175:diagnosis* / Q000453:epidemiology*; D005260:Female; D005858:Germany; D006801:Humans; D007360:Intelligence; D007859:Learning Disabilities / Q000175:diagnosis* / Q000453:epidemiology* / Q000523:psychology; D008297:Male; D008403:Mass Screening; D008433:Mathematics; D014477:Underachievement