The method of determining the average hearing threshold level across specific frequencies is a fundamental aspect of audiometry. This calculation involves summing the hearing thresholds, typically measured in decibels (dB HL), at 500 Hz, 1000 Hz, and 2000 Hz, and then dividing by three. For example, if an individual’s hearing thresholds are 20 dB HL at 500 Hz, 25 dB HL at 1000 Hz, and 30 dB HL at 2000 Hz, the resulting value is (20 + 25 + 30) / 3 = 25 dB HL. This average provides a simplified representation of hearing sensitivity in the speech frequency range.
This metric offers a quick and easily interpretable summary of a person’s hearing ability. It is valuable for screening purposes, tracking changes in hearing over time, and estimating the degree of hearing impairment. Historically, this method has served as a cornerstone of audiological assessments, providing clinicians with a standardized measure for classifying hearing loss and guiding rehabilitation strategies.