The following is meant to provide a general description of hearing testing. The hearing testing process comprises of wearing headphones or insert earphones to determine hearing sensitivity in each ear at different pitches or frequencies on a graph, called an audiogram. Decibels (dB) are listed vertically on the left of the graph (y-axis), while frequencies listed in Hertz (Hz) tested appear horizontally on the top or bottom of the graph (x-axis). Decibels is a function of loudness or volume of stimuli presented via the headphones or insert earphones, while Hertz is the measure of varying frequencies being tested. Gaining accurate information from both ears is essential for diagnosis of hearing loss.
Hearing loss is sometimes described by medical doctors in terms of percentages (ex: “My doctor told me I have a 30% hearing loss). However, describing hearing loss in terms of an arbitrary percentage does not accurately describe the functional difficulties a person may have in everyday multifaceted communications. Simply being able to hear some sounds of speech, does not equal understanding of the speech message. There are a multitude of variables involved that allow the brain to receive, interpret, and understand a speech message.
A more accurate way to describe hearing loss is by type & degree of the loss in relation to the audiogram. Type falls into three categories: sensorineural, conductive, and mixed hearing loss. Bone conduction testing is done to help determine which type of hearing loss a person has. A headband is placed behind the ear to directly test the hearing sense organ (cochlea). Noise or masking may be needed in one or both ears to individually test each ear. Degree is related to dB level on the audiogram and pertains to how much hearing loss there is. Hearing loss can range from normal hearing to mild to profound in one or both ears. All the above help project a clearer picture of how one may function with hearing aid usage.