Hearing tests explained
Published // Friday 17 June 2011
Hearing tests check a person's ability to hear the loudness and pitch of sounds. The results are charted on a graph (audiogram) helping to pinpoint the severity and causes of hearing problems. Tests include pure tone audiometry, using an audiometer, and speech discrimination tests, babies and children will receive special tests. A doctor, audiologist or ear, nose and throat specialist can provide more information about hearing loss and hearing tests.
Types of hearing loss
Hearing tests can distinguish the type of hearing loss, including:
• Conductive – a sound blockage in the middle or outer ear (or both), usually caused by middle ear infections or by wax build-up in the ear canal.
• Sensorineural – the cochlea or cochlear nerve are damaged.
• Mixed – the hearing loss is caused by a combination of conductive and sensorineural problems.
Hearing loss can also be described as:
• Congenital – when the hearing loss occurs before or just after birth. Exposure to certain diseases in utero or soon after birth can harm the hearing mechanism of the baby.
• Acquired – when the loss happens later (for example, due to disease or trauma).
Severity of hearing loss
Hearing loss is measured in decibels (dB). Conversational speech is around 65dB. The degrees of hearing loss include:
• Mild (21–45dB) – soft sounds may be difficult to distinguish.
• Moderate (46–60dB) – conversational speech is hard to hear, especially if there is background noise (such as a television or radio).
• Moderately severe (61–75dB) – it is very difficult to hear ordinary speech.
• Severe (76–90dB) – conversational speech can’t be heard.
• Profound (91dB) – almost all sounds are inaudible. Most people with profound hearing loss benefit from a hearing aid, while some don’t.
Specsavers have a great animation explaining about adult hearing tests and the process of sizing and fitting hearing aids and an overview of the benefits. View the animation here.