Type of Resources
Pure tone audiometry is the gold standard for diagnostic audiology assessments and is used to determine degree and type of hearing loss via air and bone conducted pure tones. The clinically accepted test–retest variability for pure tone audiometry is ±10 decibels (dB) (Carhart & Jerger, 1959; Landry & Green, 1999). The current study evaluated the variability in hearing thresholds for three earphones: TDH-50 supra-aural, Sennheiser HDA 200 circumaural, and Etymotic ER-2 insert phones when earphones were self-fit and when fit by an audiologist. Twenty young adult participants completed six air conducted pure tone audiometric exams for one ear using the three earphones. Testing included conventional and extended high frequency (EHF) audiometry. For each earphone, the participant fit and removed the earphone in the first trial, and the second trial was completed with the audiologist fitting and removing the earphones. A repeated measure two-way analysis of variance (ANOVA) was completed for conventional and EHF audiometry comparing hearing threshold variability, earphone, and fitter. The fitter condition did not have a statistically significant effect on hearing threshold for conventional or EHF audiometry. The type of transducer did have a statistically significant effect on hearing threshold (α = 0.05, p = 0.001); however, this effect was not considered clinically significant as the hearing threshold differences were less than 5 dB and within 10 dB of test–retest variability. This suggests that when properly instructed, patients with adequate cognitive ability and hand dexterity should be able to self-fit insert, supra-aural, and circumaural earphones.