Estimation of Measurement Uncertainty for Air Conduction Audiometry Testing by ISO 8253-1:2010
Introduction: Pure-tone audiometry is internationally standardized by ISO 8253-1 “Acoustic-Audiometric test methods—Part 1: Pure-tone air and bone-conduction audiometry.” It revised its edition in 2010, and there was the introduction of Annexure A recommending the estimated measurement uncertainly because audiometry is influenced by parameters such as repeatability , audiometer performance , transducers fitting, environment noise, masking, experience of the examiner, cooperation of the subject, and situations difficult to measure.
Objective: The study aims to estimate the uncertainty of measurement in pure-tone air audiometry according to the methodology of ISO 8253-1:2010.
Methods: Execution audiological testing repeatability with five subjects, experience of the examiner with five audiologist and only subject in the laboratory 1, and testing transducers fitting with five subjects in the laboratory 2. In the both laboratories, the level of noise control was accordance with Table 2 of ISO 8253-1. The audiometer was calibrated at the Brazilian Calibration Network with uncertainty of 1 dB and resolution in steps of 5 dB. To estimate the uncertainty, standard uncertainty was calculated, combined, and expanded.
Results: Considering the parameters of repeatability, audiometer used, ambiental noise, experience of the examiner, and transducers fitting, the expanded uncertainty values ranged between 6.3 and 7.7 dB the frequencies assessed.
Conclusion: The estimated measurement uncertainty, through the method proposed in this study value was ±10 dB. With variations in calibration, environmental noise, and inexperience of the examiner, the uncertainty can reach ±15 dB.