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A Comparison of a New Acoustic Feedback Canceller in Hearing Aids With the Current System

A Comparative, Controlled Clinical Investigation of a New Acoustic Feedback Cancellation Strategy in Comparison With the Currently Marketed System

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04146272
Enrollment
33
Registered
2019-10-31
Start date
2018-11-01
Completion date
2019-07-07
Last updated
2021-09-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Hearing Loss

Brief summary

The Purpose of the study is to show that the performance of the new feedback cancellation system is better than the feedback system used in the currently marketed hearing aids. Speech understanding should not be negatively affected by the new system, ad there should be no consequential artifacts or unwanted noises caused by the new system.

Detailed description

The amplification of sounds with a hearing aid is the most common treatment for hearing loss. Benefits of amplification and accessories used with it outweigh any risks in mild to profound hearing-impaired subjects. Hearing aids provide a benefit for people with only a mild sensorineural hearing loss. However, often people are counselled to wait to purchase hearing aids until their hearing loss becomes more significant. The benefits are obtainable for both unilateral and bilateral fittings and are both short term and durable on long term. Acoustic feedback is a critical problem to all hearing aids. The acoustic coupling between the hearing aid receiver and the microphone occurs when an endless loop is formed so that the microphone is re-amplifying sound from its own receiver. The higher the amplification of the system, the more unstable it becomes and the more likely an acoustic feedback will occur. When this happens the hearing aid user and those around them hear a loud whistling noise. A common method used to combat this problem is feedback cancellation, more specifically adaptive feedback cancellation. The goal of feedback cancellation is to quickly identify feedback path changes and make adjustments to preserve the stability of the system while maintaining a high sound quality and still providing a high stable gain compared to the gain achieved without an active feedback reduction. For this study, the Sponsor will carry out testing with participants who have hearing loss to validate the performance of the new feedback cancelling algorithm. Studies have investigated the advantages and disadvantages of different feedback cancellation techniques. However, it is accepted by professionals that having a feedback system is better than not using feedback cancellation. The Sponsor has used an adaptive feedback cancellation algorithm since 2010. For the current study the new adaptive algorithm will be compared to the current algorithm implemented in the hearing aids that are certified by the European Conformity and sold on the market. The aim is to determine if less feedback is experienced using the new system in comparison to the old system.

Interventions

DEVICEHearing Aid Mermaid Current

The current hearing aid used to treat hearing loss.

DEVICEHearing Aid Mermaid New

The new hearing aid used to treat hearing loss with an upgraded feedback cancellation system.

DEVICEPower Hearing Aid Current

The current power hearing aid used to treat strong hearing loss.

DEVICEPower Hearing Aid New

The new power hearing aid used to treat strong hearing loss with an upgraded feedback cancellation system.

Sponsors

Bernafon AG
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
SINGLE (Subject)

Masking description

The participants are masked during the lab testing. They will not know which device they are testing because the Investigator will place it on their ear without letting them see it.

Intervention model description

The participants will wear hearing aids with the current feedback system and the new feedback system each for 10 +/- 5 days. Some will wear the current hearing aids first and some will wear the new Hearing aids first.

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes

Inclusion criteria

* All classifications of hearing loss (sensorineural, conductive, mixed) * Conductive and mixed hearing loss must be approved for amplification by a physician * All shapes of hearing loss (flat, sloping, reverse slope, notch) * Severity ranging from mild to profound * German speaking * Ability and willingness to sign the consent form

Exclusion criteria

* Contraindications for amplification * Active ear disease * New hearing aid users * Inability to follow the procedures * Reduced mobility that makes then unable to attend study Appointments * Uncooperative so that it's not possible to get a valid audiogram * A strongly reduced dexterity * Central hearing disorder * Sponsor employees * Family members of Sponsor employees

Design outcomes

Primary

MeasureTime frameDescription
Change in Live Feedback Test Scores From Day 10 to Day 2010 days, 20 daysIn the lab, subjects will have the hearing aid placed in their ear. They will rate on a visual analogue scale whether feedback occurs and if so, how much annoyance it causes. The scale has a minimum of 0 and a maximum of 10. A lower score is a better answer. It will be tested in two conditions, aided with the current Hearing aid, and aided with the new Hearing aid at 10 and 20 days. The difference between the scores from day 10 and day 20 was calculated by subtracting day 20 (new hearing aid) from day 10 (current hearing aid) after both sessions of testing were completed and reported as the mean difference for the group. Regardless of the arm assignment, participants wore the same hearing aids for the lab test on days 10 and 20.

Secondary

MeasureTime frameDescription
Word Recognition - Aided20 daysSubjects will indicate on a touch screen which word that they heard through the loud speaker. The touch screen will give 5 possible answer choices that includes the correct choice and 4 other words that rhyme with the actual word. The test is run in the aided condition with the current Hearing aid and with the new Hearing aid. The test is scored by the percentage of words that they answer correctly. 0 percent is the lowest score possible and 100 percent is the highest. A higher percentage indicates a better score.
Sound Quality Rating20 daysThe subjects will complete a questionnaire that asks them to rate the quality of different aspects of the hearing aid including sound quality, own voice quality, and the sound quality when in a noisy environment. The scale is from 1 to 5 with 1 being the minimum and 5 being the maximum. A higher score indicates better quality. The questionnaire will be answered for two conditions, aided with the current Hearing aid and aided with the new Hearing aid. The difference between the scores for each condition will be calculated and reported as the mean difference across both arms (moderate hearing loss and severe hearing loss). The difference is not calculated over time points but at the end of the field trial and the assignment order of the hearing aid (new first or current first) does not bear an impact.
Word Recognition - Unaided10 daysThis measurement is made without any hearing aids. Subjects will indicate on a touch screen which word that they heard through the loud speaker. The touch screen will give 5 possible answer choices that includes the correct choice and 4 other words that rhyme with the actual word. The test is run in the unaided condition. The test is scored by the percentage of words that they answer correctly. 0 percent is the lowest score possible and 100 percent is the highest. A higher percentage indicates a better score. The scores are not dependent on the assignment order of the hearing aids (new or current first) as the measurement is made without hearing aids and a score calculated for each group (moderate or severe hearing loss) and not for each arm.-

Other

MeasureTime frameDescription
Number of Participants Reporting an Adverse Event0, 10, and 20 daysThe safety of the hearing aids will be rated by the number of adverse events reported by subjects. The minimum score is Zero and the maximum is not defined but is likely not more than 20. A lower number of adverse Events indicates a better outcome. The Outcome will be reported as the sum of Adverse Events reported across time frames.

Countries

Switzerland

Participant flow

Recruitment details

33 patients were screened for eligibility from the list of contacts at the Bernafon Hearing clinic.

Pre-assignment details

33 participants were randomized. 22 met the inclusion criteria for moderate Hearing loss and 11 for severe Hearing loss.

Participants by arm

ArmCount
Current Mermaid First, Then New
Participants were randomized to wear the current hearing aid that uses the current feedback cancellation first for 10 days. Then they wore the new Hearing aid for another 10 days.
11
New Mermaid First, Then Current
Participants were randomized to wear the new Hearing aid that uses the new feedback cancellation first for 10 days. Then they wore the current Hearing aid for another 10 days.
11
Current Power First, Then New
Participants were randomized to wear the current power hearing aid that uses the current feedback cancellation first for 10 days. Then they wore the new power Hearing aid for another 10 days.
6
New Power First, Then Current
Participants were randomized to wear the new power hearing aid that uses the new feedback cancellation first for 10 days. Then they wore the current power Hearing aid for another 10 days.
5
Total33

Baseline characteristics

CharacteristicCurrent Power First, Then NewNew Power First, Then CurrentTotalCurrent Mermaid First, Then NewNew Mermaid First, Then Current
Age, Continuous67 years67 years67 years67 years67 years
Hearing Threshold69 decibels
STANDARD_DEVIATION 10.2
71 decibels
STANDARD_DEVIATION 10.6
59 decibels
STANDARD_DEVIATION 11
47 decibels
STANDARD_DEVIATION 11.7
50 decibels
STANDARD_DEVIATION 13.1
Race and Ethnicity Not Collected0 Participants
Region of Enrollment
Switzerland
6 participants5 participants33 participants11 participants11 participants
Sex: Female, Male
Female
2 Participants1 Participants8 Participants2 Participants3 Participants
Sex: Female, Male
Male
4 Participants4 Participants25 Participants9 Participants8 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
deaths
Total, all-cause mortality
0 / 220 / 220 / 110 / 11
other
Total, other adverse events
5 / 223 / 221 / 113 / 11
serious
Total, serious adverse events
0 / 220 / 220 / 110 / 11

Outcome results

Primary

Change in Live Feedback Test Scores From Day 10 to Day 20

In the lab, subjects will have the hearing aid placed in their ear. They will rate on a visual analogue scale whether feedback occurs and if so, how much annoyance it causes. The scale has a minimum of 0 and a maximum of 10. A lower score is a better answer. It will be tested in two conditions, aided with the current Hearing aid, and aided with the new Hearing aid at 10 and 20 days. The difference between the scores from day 10 and day 20 was calculated by subtracting day 20 (new hearing aid) from day 10 (current hearing aid) after both sessions of testing were completed and reported as the mean difference for the group. Regardless of the arm assignment, participants wore the same hearing aids for the lab test on days 10 and 20.

Time frame: 10 days, 20 days

ArmMeasureValue (MEAN)Dispersion
Moderate Hearing Loss Current Mermaid First/New SecondChange in Live Feedback Test Scores From Day 10 to Day 201.7 units on a scaleStandard Deviation 2
Moderate Hearing Loss New Mermaid First/Current SecondChange in Live Feedback Test Scores From Day 10 to Day 201.7 units on a scaleStandard Deviation 2
Severe Hearing Loss Current Power First/New SecondChange in Live Feedback Test Scores From Day 10 to Day 200.1 units on a scaleStandard Deviation 1.1
Severe Hearing Loss New Power First/Current SecondChange in Live Feedback Test Scores From Day 10 to Day 200.1 units on a scaleStandard Deviation 1.1
Secondary

Sound Quality Rating

The subjects will complete a questionnaire that asks them to rate the quality of different aspects of the hearing aid including sound quality, own voice quality, and the sound quality when in a noisy environment. The scale is from 1 to 5 with 1 being the minimum and 5 being the maximum. A higher score indicates better quality. The questionnaire will be answered for two conditions, aided with the current Hearing aid and aided with the new Hearing aid. The difference between the scores for each condition will be calculated and reported as the mean difference across both arms (moderate hearing loss and severe hearing loss). The difference is not calculated over time points but at the end of the field trial and the assignment order of the hearing aid (new first or current first) does not bear an impact.

Time frame: 20 days

ArmMeasureValue (MEAN)
Moderate Hearing Loss Current Mermaid First/New SecondSound Quality Rating1.6 units on a scale
Moderate Hearing Loss New Mermaid First/Current SecondSound Quality Rating1.6 units on a scale
Severe Hearing Loss Current Power First/New SecondSound Quality Rating1.5 units on a scale
Severe Hearing Loss New Power First/Current SecondSound Quality Rating1.5 units on a scale
Secondary

Word Recognition - Aided

Subjects will indicate on a touch screen which word that they heard through the loud speaker. The touch screen will give 5 possible answer choices that includes the correct choice and 4 other words that rhyme with the actual word. The test is run in the aided condition with the current Hearing aid and with the new Hearing aid. The test is scored by the percentage of words that they answer correctly. 0 percent is the lowest score possible and 100 percent is the highest. A higher percentage indicates a better score.

Time frame: 20 days

ArmMeasureGroupValue (MEAN)Dispersion
Moderate Hearing Loss Current Mermaid First/New SecondWord Recognition - AidedCurrent hearing0.92 percentage of words correctStandard Deviation 0.34
Moderate Hearing Loss Current Mermaid First/New SecondWord Recognition - AidedNew hearing aid0.91 percentage of words correctStandard Deviation 0.35
Moderate Hearing Loss New Mermaid First/Current SecondWord Recognition - AidedNew hearing aid0.91 percentage of words correctStandard Deviation 0.35
Moderate Hearing Loss New Mermaid First/Current SecondWord Recognition - AidedCurrent hearing0.92 percentage of words correctStandard Deviation 0.34
Severe Hearing Loss Current Power First/New SecondWord Recognition - AidedNew hearing aid0.78 percentage of words correctStandard Deviation 0.48
Severe Hearing Loss Current Power First/New SecondWord Recognition - AidedCurrent hearing0.77 percentage of words correctStandard Deviation 0.49
Severe Hearing Loss New Power First/Current SecondWord Recognition - AidedNew hearing aid0.78 percentage of words correctStandard Deviation 0.48
Severe Hearing Loss New Power First/Current SecondWord Recognition - AidedCurrent hearing0.77 percentage of words correctStandard Deviation 0.49
Secondary

Word Recognition - Unaided

This measurement is made without any hearing aids. Subjects will indicate on a touch screen which word that they heard through the loud speaker. The touch screen will give 5 possible answer choices that includes the correct choice and 4 other words that rhyme with the actual word. The test is run in the unaided condition. The test is scored by the percentage of words that they answer correctly. 0 percent is the lowest score possible and 100 percent is the highest. A higher percentage indicates a better score. The scores are not dependent on the assignment order of the hearing aids (new or current first) as the measurement is made without hearing aids and a score calculated for each group (moderate or severe hearing loss) and not for each arm.-

Time frame: 10 days

ArmMeasureValue (MEAN)Dispersion
Moderate Hearing Loss Current Mermaid First/New SecondWord Recognition - Unaided0.79 percentage of words correctStandard Deviation 0.48
Moderate Hearing Loss New Mermaid First/Current SecondWord Recognition - Unaided0.79 percentage of words correctStandard Deviation 0.48
Severe Hearing Loss Current Power First/New SecondWord Recognition - Unaided0.40 percentage of words correctStandard Deviation 0.58
Severe Hearing Loss New Power First/Current SecondWord Recognition - Unaided0.40 percentage of words correctStandard Deviation 0.58
Other Pre-specified

Number of Participants Reporting an Adverse Event

The safety of the hearing aids will be rated by the number of adverse events reported by subjects. The minimum score is Zero and the maximum is not defined but is likely not more than 20. A lower number of adverse Events indicates a better outcome. The Outcome will be reported as the sum of Adverse Events reported across time frames.

Time frame: 0, 10, and 20 days

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Moderate Hearing Loss Current Mermaid First/New SecondNumber of Participants Reporting an Adverse Event5 Participants
Moderate Hearing Loss New Mermaid First/Current SecondNumber of Participants Reporting an Adverse Event3 Participants
Severe Hearing Loss Current Power First/New SecondNumber of Participants Reporting an Adverse Event1 Participants
Severe Hearing Loss New Power First/Current SecondNumber of Participants Reporting an Adverse Event3 Participants

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026