In 30 per cent of PCTs, health visitors attached to GP surgeries will test babies in the surgery or during a home visit. In the remainder, specialised screening staff will test newborns in hospital before discharge.
The automated otoacoustic emissions (AOAE) test used involves placing a small earpiece into the baby's ear canal. A click is produced, and a microphone picks up the noise hair cells within the cochlea make in response.
If the AOAE test is inconclusive, the automated auditory brainstem response test is used. The same click stimulus is used, this time using ear muffs, and sensors on the head and neck detect the electrical response in the auditory nerve to the brain. If both tests suggest hearing loss, an audiology referral is made.
It is hoped that the system will prevent GPs from having to be involved in lengthy discussion with parents over whether a baby needs to be referred because of possible hearing problems.
In Wales, a similar programme has been fully running since 2005. Scotland is finalising plans for the roll-out of its service.