Improving audiometric thresholds by changing the headphone position at the ear

A 10-year noise project, consisting of annual hearing measurement, temporary threshold shift (TTS) measurements and examination of noise exposure in 250-300 employees, involved a study of the improvement in measured hearing threshold by changing the position of the headphone at the ear. Threshold measurements were performed at 11 frequencies ranging from 125 to 8,000 Hz, and consisted of 2,708 audiograms in the hearing control program and 551 audiograms in the TTS program. A new threshold determination at frequencies above 3,000 Hz was carried out after moving the earphone to a new position in 870 (32%) of the cases in the hearing measurement program and 248 (45%) of those in the TTS program. The indication for moving the phone is discussed. Improved thresholds in the range of 5-40 dB at 6,000 and 8,000 Hz were observed in 58-68% of the cases, depending upon frequency and program (measurement of hearing and TTS). Consequences for standard threshold values and for diagnostic purposes are discussed.