title: Comorbidity between ADDH and learning disability: a review and report in a clinically referred sample.
abstract: A widely variable overlap ranging from 10 to 92% has been reported in the literature between attention deficit disorder with hyperactivity (ADDH) and learning disability (LD), most likely a result of inconsistencies in the criteria used to define LD in different studies. The following study seeks to more accurately determine rates of LD in clinically referred children. Using a psychometrically reliable methodological approach, it was expected that the rate of LD in ADDH children would be far more modest than previously reported. Subjects were referred children with ADDH (N = 60), children with academic problems (N = 30), and normal controls (N = 36) of both sexes with available psychological and achievement testing. Using a liberal definition of LD, significant differences were found between the groups (ADDH = 38% versus academic problems = 43% versus normals = 8%; p = 0.002). In contrast, more modest rates were found using two more stringent methods of assessment (23 and 17%; 10 and 3%; 2 and 0%, respectively; p = 0.02). Arithmetic-based LD appears to be equally identified by both stringent methods, whereas the liberal definition overidentified children in all three groups. These findings show that a liberal definition of LD overidentifies LD not only in ADDH children but also in normal children.
authors.affiliation: Department of Psychiatry, Massachusetts General Hospital, Boston 02114.
authors.forename: M
authors.initials: M
authors.lastname: Semrud-Clikeman
authors.forename: J
authors.initials: J
authors.lastname: Biederman
authors.forename: S
authors.initials: S
authors.lastname: Sprich-Buckminster
authors.forename: B K
authors.initials: BK
authors.lastname: Lehman
authors.forename: S V
authors.initials: SV
authors.lastname: Faraone
authors.forename: D
authors.initials: D
authors.lastname: Norman
mesh_terms: D000124:Achievement; D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology; D002648:Child; D015897:Comorbidity; D003430:Cross-Sectional Studies; D004410:Dyslexia / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology; D005260:Female; D006801:Humans; D015994:Incidence; D007859:Learning Disabilities / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology; D008297:Male; D011569:Psychiatric Status Rating Scales; D014481:United States / Q000453:epidemiology