The Reliability of Repeated Auditory Threshold Determination

Abstract

This paper considers the precision which may be expected in short-term serial measurements of audiometric thresholds.Twelve otologically normal young men were tested on four separate occasions at 1, 2, 3, 4, 6, 8, 0-5, and 1 kc/s. The tests were carried out in a mobile test room installed in a specially constructed vehicle chassis.The acoustic output of the audiometer and ear-phones was measured at intervals throughout the investigation. Output stability with variations of mains supply voltage and drift during the warming-up period of the instrument were also measured.It was concluded that the instrument variation had been extremely slight throughout the investigation.The estimates of variance of repeated threshold determinations on a single ear were found to be 8 5 (dB)2 at 0 5 kc/s, 6 (dB)2 at 3 kc/s, and 23 (dB)2 at 8 kc/s. Differences between consecutive determinations extended to 25 dB.These results were obtained under conditions which practically precluded all sources of variation other than that due to the inherent uncertainty of audiometric measurements. It appears to follow, therefore, that if an apparent drop in auditory threshold in one ear is to be considered as significant evidence (P = 1 %) of a real change, the difference would have to be at least The subjects were 12 male medical students in whom no ear, nose or throat pathology could be demonstrated and who gave no history of noise exposure. Attention was paid to the possibility of the subjects developing rhinitis, either coryzal or allergic in origin, during the course of the experiment. As far as is known no test was carried out on a subject suffering from either of these conditions. The possibility of a temporary threshold shift resulting from the recent use of noisy transport was also excluded by arranging to perform the tests between lectures, rather than on the individual's first arrival in the morning. Enquiry was also made concerning previous treatment by drugs with VlIIth nerve toxicity.It was considered that this group comprised otologically normal subjects as defined in British Standards 2497 (1954) and this assumption is supported by the actual audiometric results, which showed no gross departure from the normal threshold of hearing.For the purpose of this experiment it was necessary to demonstrate that the acoustic output of the audiometer did not vary during the course of the 231 on 11 May 2018 by guest. Protected by copyright.

Auditory filter asymmetry at 2000 Hz in 80 normal-hearing ears

“…The ages of the subjects ranged from 18-24 years here, 47-72 years for Glasberg and Moore, and approximately 25-75 years for Patterson et al and Glasberg et al Pick et al did not provide the ages of their subjects. Finally, caution is advised in interpreting the correlations with quiet threshold because of the difficulty of precisely defining the noise floor, the high variability across repeated measurements of quiet threshold ͑e.g., Atherley and Dingwall-Fordyce, 1963͒, and the possible influence of threshold microstructure ͑e.g., Elliot, 1958͒ on the results.…”

A user-operated audiometry method based on the maximum likelihood principle and the two-alternative forced-choice paradigm

“…For otologically-normal subjects SDdiffs of traditional audiometry have been reported between 4 -8 dB but exceeding 5 dB for frequencies above 4000 Hz (Burns & Hinchcliffe, 1957;Atherley & Dingwall-Fordyce, 1963), whereas serial testing of hearingimpaired subjects resulted in similar SDdiffs between 4 -7 dB (Ho et al, 2009;Margolis et al, 2010). The variability must be as low as possible during serial testing in a hearing conservation programme and SDdiffs have been reported between 4 -7 dB in A negative value indicates that user-operated hearing thresholds are lower than corresponding hearing thresholds obtained with traditional audiometry.…”

“…The standard deviation of differences (SDdiff) is the best parameter to describe the test-retest threshold variability between two methods in serial testing (Dobie, 1983).Typical SDdiffs from manual audiometry as well as self-recording audiometry are around 3 -7 dB (Burns & Hinchcliffe, 1957;Atherley & Dingwall-Fordyce, 1963;Erlandsson et al, 1979;Lutman et al, 1989;Ho et al, 2009). For automated audiometry SDdiffs have been reported around 5 -8 dB (Ho et al, 2009;Eikelboom et al, 2013).…”

Repeatability of High-Frequency Distortion-Product Otoacoustic Emissions in Normal-Hearing Adults

“…Thus, highfrequency DPOAEs can be examined further as a monitoring tool for those exposed to noise or undergoing ototoxic treatments to determine if changes in cochlear status, that are known to affect the higher frequencies first, have occurred. Atherly (1963) examined test-retest variability of audiometric thresholds and found normal variability occurred as independent shifts at random frequencies. Thus, shifts at adjacent test frequencies would indicate a more systematic change and increase the likelihood of a true decrease in sensitivity (Dobie, 1983;Fausti, Henry, Helt et al, 1999).…”