Self-assessment of bone conduction hearing threshold using mobile audiometry: comparison with pure tone audiometry

The aim of the research was to evaluate the feasibility of measuring the bone conduction hearing threshold using self-administered mobile audiometry.
A single-centre, closed, cross-over trial was carried out on patients from the ENT Department. A mobile-based, self-administered, audiologist-assisted assessment of the bone conduction hearing threshold was carried out by means of the open-access, freeware app Hearing Test using two types of bone conduction headphones: professional B71 bone transducer and commercially available AfterShokz Openmove open-ear headphones.
Seventy-seven ears.
A test-retest examination revealed the lowest standard deviation for open-ear headphones at 3.33 dB (95% CI 2.92–3.79). When compared with pure tone audiometry, the intraclass correlations of 0.95 (95% CI 0.94–0.96) and 0.90 (95% CI 0.88–0.92) were obtained for the bone transducer and for the open-ear headphones, indicating excellent and good reliability, respectively. However, the regression slope of 0.67 was found for the air-bone gap when using open ear headphones, which was significantly different from 1 (p < 0.001).
Open-ear headphones provide an alternative for estimating bone conduction once the air-bone gap has been adjusted by a factor of 1/0.6 7 ≅1.5. They demonstrate improved reproducibility over the bone transducer and are much easier to use with a mobile device. Trial Registration: Wroclaw Medical University, Science Support Centre, BW60/2020

本研究旨在评估采用自行施测的移动听力学检测（mobile audiometry）手段测量骨传导听阈（bone conduction hearing threshold）的可行性。
本研究为单中心、封闭交叉试验，于耳鼻咽喉科（Ear, Nose and Throat, ENT）患者群体中开展。研究通过开源免费移动应用《Hearing Test》，搭配专业B71骨传导换能器（bone transducer）与市售AfterShokz Openmove开放式耳机两款骨传导设备，由听力学专家辅助完成基于移动设备的自行施测骨传导听阈评估。
本研究共纳入77耳。
重测分析结果显示，开放式耳机的测量标准差最低，为3.33 dB（95%置信区间CI：2.92~3.79）。与纯音测听（pure tone audiometry）结果对比时，骨传导换能器与开放式耳机的组内相关系数（intraclass correlations）分别为0.95（95%CI：0.94~0.96）与0.90（95%CI：0.88~0.92），分别提示极佳与良好的测量信度。
不过，使用开放式耳机时，气骨导差（air-bone gap）的回归斜率为0.67，与理论值1存在显著统计学差异（p<0.001）。
经1/0.67≅1.5的系数校正气骨导差后，开放式耳机可作为骨传导听阈评估的替代方案。相较于骨传导换能器，其测量再现性更优，且在移动设备上的使用便捷性显著提升。
试验注册：弗罗茨瓦夫医科大学科研支持中心，BW60/2020