title: Hearing impairment: a population study of age at diagnosis, severity, and language outcomes at 7-8 years.
abstract: BACKGROUND
  Better language outcomes are reported for preschool children with hearing impairment (HI) diagnosed very early, irrespective of severity. However, population studies of older children are required to substantiate longer term benefits of early detection.
  
  
  OBJECTIVE
  To study impact of age of diagnosis and severity of HI in a population cohort of 7-8 year old children.
  
  
  METHODS
  Eighty eight 7-8 year old children born in Victoria, who were (a) fitted with hearing aids for congenital HI by 4.5 years and (b) did not have intellectual or major physical disability were studied. Main outcome measures were Clinical Evaluation of Language Fundamentals (CELF) and Peabody Picture Vocabulary Test (PPVT). Predictors were pure tone average (0.5, 1, 2 kHz) in better ear at diagnosis and age at diagnosis. Marginal (adjusted) means were estimated with general linear models.
  
  
  RESULTS
  Response rate was 67% (n = 89; 53 boys). Mean age at diagnosis was 21.6 months (SD 14.4); 21% had mild, 34% moderate, 21% severe, and 24% profound HI; mean non-verbal IQ was 104.6 (SD 16.7). Mean total CELF score was 76.7 (SD 21.4) and mean PPVT score 78.1 (SD 18.1). Age of diagnosis, adjusted for severity and IQ, did not contribute to language scores. In contrast, adjusted mean CELF and PPVT language scores fell sequentially with increasing severity of HI.
  
  
  CONCLUSIONS
  More severe HI, but not later diagnosis, was strongly related to poorer language outcomes at 7-8 years. Further systematic study is needed to understand why children with hearing impairment have good or poor outcomes.
authors.affiliation: Centre for Community Child Health, Murdoch Childrens Research Institute, Melbourne, Australia. melissa.wake@rch.org.au
authors.forename: M
authors.initials: M
authors.lastname: Wake
authors.forename: Z
authors.initials: Z
authors.lastname: Poulakis
authors.forename: E K
authors.initials: EK
authors.lastname: Hughes
authors.forename: C
authors.initials: C
authors.lastname: Carey-Sargeant
authors.forename: F W
authors.initials: FW
authors.lastname: Rickards
mesh_terms: D017668:Age of Onset; D000704:Analysis of Variance; D002648:Child; D015331:Cohort Studies; D005260:Female; D006304:Health Status; D006311:Hearing Disorders / Q000151:congenital / Q000175:diagnosis* / Q000523:psychology; D006801:Humans; D007806:Language Disorders / Q000209:etiology* / Q000517:prevention & control; D008297:Male; D011379:Prognosis; D011932:Reading; D012044:Regression Analysis; D011795:Surveys and Questionnaires; D014739:Victoria
references.citation: Int J Audiol. 2003 Oct;42(7):385-90
references.pmid: 14582634
references.citation: Int J Pediatr Otorhinolaryngol. 1998 Aug 1O;44(3):309-10
references.pmid: 9780076
references.citation: Int J Lang Commun Disord. 1999 Jul-Sep;34(3):243-64
references.pmid: 10884901
references.citation: JAMA. 2001 Oct 24-31;286(16):2000-10
references.pmid: 11667937
references.citation: Audiol Neurootol. 2002 Mar-Apr;7(2):114-21
references.pmid: 12006739
references.citation: Ann Otol Rhinol Laryngol Suppl. 2002 May;189:74-8
references.pmid: 12018355
references.citation: Pediatrics. 1998 Nov;102(5):1161-71
references.pmid: 9794949
references.citation: Br J Audiol. 1986 May;20(2):165-7
references.pmid: 3719164
references.citation: Br J Audiol. 1992 Apr;26(2):97-107
references.pmid: 1628121
references.citation: Arch Dis Child. 1995 Jan;72(1):11-5
references.pmid: 7717729
references.citation: Br J Audiol. 1995 Dec;29(6):315-34
references.pmid: 8861408