title: Six year effectiveness of a population based two tier infant hearing screening programme.
abstract: OBJECTIVE
  To determine whether a two tier universal infant hearing screening programme (population based risk factor ascertainment and universal distraction testing) lowered median age of diagnosis of bilateral congenital hearing impairment (CHI) >40 dB HL in Victoria, Australia.
  
  
  METHODS
  Comparison of whole population birth cohorts pre and post introduction of the Victorian Infant Hearing Screening Program (VIHSP). All babies surviving the neonatal period born in Victoria in 1989 (pre-VIHSP) and 1993 (post-VIHSP) were studied. (1) Pre-1992: distraction test at 7-9 months. (2) Post-1992: infants with risk factors for CHI referred for auditory brain stem evoked response (ABR) assessment; all others screened by modified distraction test at 7-9 months.
  
  
  RESULTS
  Of the 1989 cohort (n = 63 454), 1.65/1000 were fitted with hearing aids for CHI by end 1995, compared with 2.09/1000 of the 1993 cohort (n = 64 116) by end 1999. Of these, 79 cases from the 1989 cohort (1.24/1000) and 72 cases from the 1993 cohort (1.12/1000) had CHI >40 dB HL. Median age at diagnosis of CHI >40 dB HL for the 1989 birth cohort was 20.3 months, and for the 1993 cohort was 14.2 months. Median age at diagnosis fell significantly for severe CHI but not for moderate or profound CHI. Significantly more babies with CHI >40 dB HL were diagnosed by 6 months of age in 1993 than in 1989 (21.7% v 6.3%). Compared to the six years pre-VIHSP, numbers aided by six months were consistently higher in the six years post-VIHSP (1.05 per 100 000 births versus 13.4 per 100 000 births per year).
  
  
  CONCLUSIONS
  VIHSP resulted in very early diagnosis for more infants and lowered median age of diagnosis of severe CHI. However, overall results were disappointing.
authors.affiliation: Centre for Community Child Health, Royal Children's Hospital, Melbourne, Australia.
authors.forename: S A
authors.initials: SA
authors.lastname: Russ
authors.forename: F
authors.initials: F
authors.lastname: Rickards
authors.forename: Z
authors.initials: Z
authors.lastname: Poulakis
authors.forename: M
authors.initials: M
authors.lastname: Barker
authors.forename: K
authors.initials: K
authors.lastname: Saunders
authors.forename: M
authors.initials: M
authors.lastname: Wake
mesh_terms: D017668:Age of Onset; D001300:Audiometry, Evoked Response; D015331:Cohort Studies; D006310:Hearing Aids; D006311:Hearing Disorders / Q000151:congenital / Q000175:diagnosis*; D006320:Hearing Tests / Q000379:methods; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D015997:Neonatal Screening / Q000379:methods / Q000592:standards*; D011379:Prognosis; D012017:Referral and Consultation; D012307:Risk Factors; D014739:Victoria