Confirmation of impairment may be delayed in some cases. Delayed confirmation of children with congenital impairments has certainly been the case in the past. Earlier confirmation and intervention, by 6 months of age, has been shown to lead to improved outcomes¹ and is a major argument for neonatal hearing screening.

However, if all of the rise not attributed to acquired impairment was accounted for by delayed identification, then the yield we see from universal neonatal hearing screening would be close to the aggregate prevalence in slides 10 and 11. The yield from well-conducted universal screening programmes in the UK is only 1.06/1000 (ci 0.84-1.44) - close to the prevalence reported here for the youngest cohort (1995), and the upper confidence limit (1.44) falls outside the confidence limits for both observed (1.62) and adjusted (2.02) prevalence.