Is it valid to calculate the 3-kilohertz threshold by averaging 2 and 4 kilohertz?
Many guidelines for reporting hearing results use the threshold at 3 kilohertz (kHz), a frequency not measured routinely. This study assessed the validity of estimating the missing 3-kHz threshold by averaging the measured thresholds at 2 and 4 kHz. The estimated threshold was compared to the measured threshold at 3 kHz individually and when used in the pure-tone average (PTA) of 0.5, 1, 2, and 3 kHz in audiometric data from 2170 patients. The difference between the estimated and measured thresholds for 3 kHz was within ± 5 dB in 72% of audiograms, ± 10 dB in 91%, and within ± 20 dB in 99% (correlation coefficient r = 0.965). The difference between the PTA threshold using the estimated threshold compared with using the measured threshold at 3 kHz was within ± 5 dB in 99% of audiograms (r = 0.997). The estimated threshold accurately approximates the measured threshold at 3 kHz, especially when incorporated into the PTA.
Department of Otolaryngology-Head and Neck Surgery, Stanford University, Stanford, California 94305-5739, USA. rgurgel@ohns.stanford.edu
Richard K
RK
Gurgel
Gerald R
GR
Popelka
John S
JS
Oghalai
Nikolas H
NH
Blevins
Kay W
KW
Chang
Robert K
RK
Jackler
D001301:Audiometry, Pure-Tone / Q000379:methods* / Q000706:statistics & numerical data; D001309:Auditory Threshold; D003951:Diagnostic Errors; D006801:Humans; D008433:Mathematics; D015203:Reproducibility of Results