When hearing loss is suspected, Pure Tone Audiometry (PTA) Test is the most basic and common type of hearing test used to evaluate hearing loss in an individual. This is done by checking one’s response to sounds presented at certain frequencies and volume. PTA tests are conducted to obtain the hearing thresholds of individuals, allowing the audiologist to gain insights on what the softest levels of sound the person can hear at different pitches of sounds.
During the test, individuals will respond by pressing a button or raising a hand after hearing a series of sounds presented on each ear through a pair of headphones. The results of the hearing test will be plotted in a graph known as an audiogram. Audiogram results will provide insights on the type and the severity of hearing loss the individual is experiencing.
PTA is performed with the use of an audiometer. Handheld audiometers have a sensitivity of 92 percent and a specificity of 94 percent in detecting sensorineural hearing impairment, which in other words are highly accurate and effective medical devices. There are several types of audiometers available, but all function similarly by allowing the audiologist to increase and decrease the intensity (loudness, in decibels [dB]) and frequency (pitch, in Hz) of the signal as desired.
PTA is broadly defined as either a screening or a threshold search. Screening audiometry presents sounds across the speech spectrum (250 to 8,000 Hz) at the upper limits of normal hearing (25 to 30 dB for adults, and 15 to 20 dB for children). Results are recorded as either a pass, indicating that the patient’s hearing levels are within normal limits, or as a refer, indicating that hearing loss is possible and a repeat screening test or a threshold search test is recommended.
PTA is non-invasive and painless, and generally takes around 20 to 30 minutes to complete. These hearing tests can be done at hearing specialist clinics, or at hospitals. The elderly are encouraged to go for hearing tests once every 3 to 5 years as part of their routine body check-ups, since age-related hearing loss are common and they often happen gradually overtime due to one’s natural aging process.
Individuals who are constantly exposed to loud noises and or are working in noisy environments (e.g. factories, construction, nightclubs, concerts) should also go for regular hearing tests as constant exposure to loud noises without proper care can lead to noise-induced hearing loss, such as conductive hearing loss or sensorineural hearing loss.