Related Experiment Video
Updated: Jul 9, 2025

Systematic Hearing Performance Evaluation Process for Adolescents with Cochlear Implantation at Early Ages
Published on: March 24, 2023
Comparing Direct-to-Consumer Devices to Hearing Aids: Amplification Accuracy for Three Types of Hearing Loss
Sterling W Sheffield1, Molly Jacobs2, Charles Ellis1
1Department of Speech, Language, and Hearing Sciences, University of Florida, Gainesville.
Purpose:
The U.S. Food and Drug Administration finalized regulations for over-the-counter hearing aids (OTC-HAs) on August 17, 2022. Little is known about the comparative performance of OTC-HAs and prescription HAs. This study compared amplification accuracy of prescription HAs and direct-to-consumer devices (DTCDs, including personal sound amplification products [PSAPs] and OTC-HAs).
Method:
Eleven devices were programmed to meet prescriptive targets in an acoustic manikin for three degrees of hearing loss. Devices consisted of high- and low-end HAs, PSAPS, and OTC-HAs. Each was tested, and deviations from target measured with an HA analyzer at every combination of 10 frequencies and low-, average-, and high-level inputs. Accuracy was compared using a multilevel Poisson model with device-specific intercepts controlling for input level, frequency, and device type.
Results:
For mild-moderate hearing loss, deviations from targets were not statistically different between high- and low-end HAs, but PSAPs (5.50 dB, SE = 0.92 dB) and OTC-HAs (8.83 dB, SE = 1.10 dB) had larger differentials. For flat moderate hearing loss, compared to high-end HAs, average differentials were larger for all device types at all input levels and frequencies (Low HA: 3.82 dB, SE = 1.10 dB; PSAP: 9.24 dB, SE = 1.22 dB; OTC-HA: 8.61 dB, SE = 1.19 dB). For mild sloping to severe hearing loss, compared to high-end HAs, OTC-HAs (9.72 dB, SE = 1.20 dB) and PSAPs (7.34 dB, SE = 1.07 dB) had larger differentials and significant variability at the highest and lowest frequencies. Half (three) of the PSAPs and OTC-HAs met most targets within ±5 dB.
Conclusions:
DTCDs were unable to meet prescriptive targets for severe types of hearing loss but could meet them for mild hearing loss. This study provides an examination of current hearing devices. More research is needed to determine whether meeting prescriptive targets provides any benefit in the outcomes and performance with DTCD devices.
Related Concept Videos
Instrumentation Amplifier
To overcome this challenge, an ECG machine utilizes an instrumentation amplifier. This specialized amplifier is...
Sum and Difference OpAmps
A summing amplifier, or an adder, utilizes an op-amp to merge multiple input signals into a single output signal. When audio signals are introduced into its input channels, the input resistors initiate currents that traverse feedback resistors, resulting in an output voltage. Applying Kirchhoff's...
Design Example: Vintage Mixing Console
The specifications for the pre-amplifier were clear. It needed to amplify the audio signal by a factor of 10, have an input impedance above 10...
Characteristics of Practical Op Amps
The ratio of differential gain to the common-mode gain is defined as the common-mode rejection ratio (CMRR). This ratio quantifies the ability of operational amplifiers (op-amps) to reject common-mode...

