Smartphone-facilitated in-situ audiometry for community-based hearing testing

Authors: Caitlin Frisby1 (University of Pretoria)*; Karina C De Sousa1; Robert Eikelboom2; Faheema Mahomed-Asmail1; David Moore3; Tersia de Kock4; Vinaya Manchaiah5; De Wet Swanepoel1

1University of Pretoria

2Ear Science Institute

3Cincinnati Children’s Hospital Medical Center

4hearX Foundation

5University of Colorado School of Medicine


Background Scalable service-delivery models utilising innovative technologies and task-shifting could improve access to hearing care. This study aimed to determine the validity of automated smartphone-facilitated in-situ audiometry for community-based hearing testing.

Method Experiment 1: 15 adult participants were evaluated according to the ISO 8253-1 (2010) standards to determine MPANLs for Peltor 3M earcups covering hearing aids with in-situ capabilities. Experiment 2: Frequency and intensity output of 14 same-model hearing aids were measured to determine inter-device reliability. Experiment 3: 85 adult participants were tested in a soundproof booth to determine accuracy and test-retest reliability of automated in-situ air conduction (AC) pure tone audiometry (PTA) performed independently compared to clinical AC PTA facilitated by an audiologist. The first 39 participants were tested twice to determine test-retest reliability. Experiment 4: In a community setting, 144 adult participants were tested by CHWs to compare in-situ audiometry covered by circumaural Peltor 3M earcups to automated AC PTA

Results Experiment 1: MPANLs of the Peltor 3M earcups, when covering Lexie Lumens, are higher than the MPANLs of standard headphones and range from 24 to 47.3 dB. Experiment 2: Inter-device performance reliability was high, with the average difference across all hearing aids at each intensity less than 3dB across all frequencies. Experiments 3 and 4: Most automated in-situ audiometry hearing thresholds obtained in a soundproof booth (85%) and a community setting (83%) across all frequencies were within 10 dB of clinical and automated AC PTA

Conclusion Automated in-situ audiometry covered by circumaural earcups allows for community testing and yields reliable and valid results. Due to automation, in-situ audiometry can be facilitated by CHWs. Automated in-situ audiometry has the potential to revolutionise access to hearing healthcare, especially in LMICs