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Direct-to-Consumer Hearing Devices: Capabilities, Costs, and Cosmetics
Ibrahim Almufarrij1,2, Kevin J Munro1,3, Piers Dawes1,3
11 Manchester Centre for Audiology and Deafness, School of Health Sciences, UK.
Trends in Hearing
|July 9, 2019
Summary
Direct-to-consumer (DTC) hearing devices often underperform compared to National Health Service (NHS) hearing aids. Many DTC devices exhibit poor technical performance and cosmetic appeal, potentially leading to unsatisfactory sound quality.
Area of Science:
- Audiology
- Consumer Health Technology
- Medical Device Evaluation
Background:
- Direct-to-consumer (DTC) hearing devices offer an accessible alternative to traditional hearing aids, bypassing professional consultation.
- The increasing availability of DTC devices necessitates an evaluation of their performance against established standards.
Purpose of the Study:
- To compare the technical performance and user-perceived cosmetic acceptability of 28 DTC hearing devices against a UK National Health Service (NHS) hearing aid.
- To assess the ability of DTC devices to meet standard audiological gain and slope targets for mild and moderate hearing losses.
Main Methods:
- Electroacoustic performance was measured using a 2-cc coupler and a Knowles Electronic Manikin for Acoustic Research.
- A blinded, paired comparison was conducted online with 126 participants evaluating cosmetic appearance and willingness-to-wear.
- Devices were tested for their match to prescribed gain and slope targets for common hearing loss profiles.
Main Results:
- Higher priced DTC devices generally showed better performance in matching prescribed targets, with lower distortion and wider bandwidth.
- On all measured parameters, some DTC devices performed worse than the NHS reference device.
- Most DTC devices were rated lower for aesthetics and had significantly different gain-frequency responses and output levels compared to prescriptions.
Conclusions:
- Many DTC hearing devices fail to meet essential electroacoustic and aesthetic benchmarks when compared to NHS hearing aids.
- The flexibility and performance limitations of DTC devices pose a risk of poor sound quality and potentially unsafe loudness levels.
- Manufacturers face the challenge of developing affordable DTC hearing solutions with improved cosmetic appeal and accurate electroacoustic characteristics.
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