All children in the UK have a hearing test as part of the newborn hearing screening programme run by the NHS. Most hearing conditions develop in childhood but some may develop in adulthood; usually, different tests are used for children and adults.
Some of the most common types of hearing tests are outlined below:
Children’s hearing tests
OAE test (otoacoustic emissions test)
This test is usually carried out as part of the newborn hearing screening programme; it is a very quick, simple and painless test. The test involves inserting a tiny probe into the baby’s ear; the probe generates a sound that is heard by the baby’s ear; the ear then produces an echo in response to the sound (this is known as the otoacoustic emission). The echo produced by the baby’s ear will be measured on a computer; babies with good hearing will register an echo and those that have do not register any echo will usually be referred for further testing (it is important to note that having no echo does not necessarily mean your baby has hearing problems).
ABR test (auditory brainstem response test)
The auditory brainstem response test involves measuring a baby’s response to noises and sounds that the baby hears via headphones that are placed over their ears; the responses are shown on a computer. The test is usually carried out at the audiology department of a hospital; this unit specialises in hearing problems. The strength of the baby’s responses is used to indicate whether or not they have hearing difficulties.
IDT (infant distraction test)
The infant distraction test is usually used on slightly older babies; the test involves measuring responses and assessing the baby’s ability to identify the direction of noises and sounds. The IDT test is usually carried out on babies aged around 7 months old. During the test, the baby will be tested to see if they can react to where a sound has come from; this involves a tester making noises from a position that is out of the baby’s sight; another tester may be used to help to keep the baby’s full attention. This test is not used as often as it used to be as it only gives a general impression of a baby’s hearing, rather than providing accurate results.
Pure tone audiometry test
The pure tone audiometry test is usually carried out before children go to school. It uses a device known as an audiometer to generate sounds of different frequencies and volumes; children will wear a pair of headphones and will register that they have heard the sound by pressing a button. If the child fails to respond to a lot of the sounds they may be referred to a hearing specialist.
The tympanometry test is used to determine how flexible a child’s eardrum is. The test involves inserting a thin tube into the child’s ear; air is then blown into the tube. In order to have good hearing, a child should have a flexible eardrum. This test can be used to diagnose glue ear, which is a common condition caused by a build up of fluid in the ear.
VRA test (visual reinforcement audiometry)
The visual audiometry test is used on babies and young children aged between 7 months and 2 years old. It is similar to the infant distraction test because it tests the child’s reaction to sound. During the test, sounds of varying frequency and volume will be played into the room through speakers; the child will then be observed to see if they move as a response to the sounds. This test is usually carried out in the audiology department of a hospital.
Adult hearing tests:
Many adults experience problems with their hearing, especially those over the age of 55; when a patient goes to a doctor with a hearing problem, there are a number of different tests they may carry out to determine the cause and the severity of the problem. The most common tests are outlined below:
Physical examination of the ear
This is usually the first step taken by a doctor or specialist when a patient complains of hearing problems; the physical examination is used to identify possible causes of the problems such as fluid inside the ear, an obstruction that may be blocking the ear, a hole in the eardrum or discharge coming out of the ear. The examination is carried out using an instrument called an auriscope; this instrument has a light on the end, which allows the doctor to see inside the ear. During the consultation the doctor will usually ask questions about the patient’s symptoms and when they first started experiencing difficulties with their hearing. If a cause, such as those listed above, is identified then the doctor will either refer the patient for specialist care or prescribe medication to treat the problem; the patient’s hearing will then be tested again once the treatment is completed.
Tuning fork test
The tuning fork test involves using tuning forks to generate sounds of varying pitch; the doctor will hit the tuning fork against an object to generate the sound and then hold the forks up at the side of the patient’s head; the patient will then discuss how well they can hear the sounds with the doctor. In some cases the forks may be held against the mastoid bone, which is located behind the ear; this test is used to determine how well the patient can hear when the sound waves come into the ear from the mastoid bone.
This is a quick and simple test where the patient will be asked to repeat a word that is whispered into their ear by a doctor or nurse; one ear will be covered while the other is being tested.
Bone oscillator test
This works in a similar way to the tuning fork test when the forks are placed against the mastoid bone. The bone oscillator test is also used to determine how well the patient can hear sounds that are transmitted via waves from the bone into the ear. Instead of using a tuning fork, the doctor will use an instrument known as a bone oscillator; this will be positioned against the mastoid bone.