Confirmation and intervention by 6 months of age have been demonstrated to result in improved outcomes yet the median age of confirmation of congenital impairments has exceeded 18 months even in regions with good paediatric audiology services.

Many countries throughout the world are therefore introducing hearing screening programmes designed to identify children born with a hearing impairment as early as possible. In England a programme of Universal Newborn Hearing Screening (UNHS) began implementation in 2002.

Effectiveness of a screening programme in identifying true cases must be based on a knowledge of the anticipated number of cases. This knowledge comes from epidemiological studies which produce estimates of prevalence.

1. Downs MP, Yoshinago-Itano C. The efficacy of early identification and intervention for children with hearing impairment. Pediatr Clin N Am 1999;46:79-87