Evaluation of BiCROS Fitting Benefits

Evaluate the Benefit of a BiCROS Hearing Aid Fitting

22 candidates for BiCROS hearing aids will be recruited and fitted with a hearing aid and a CROS device. Following a real-world trial, each participant will be tested on a range of outcome measures including speech recognition in noise, ratings of listening effort, and ratings of preference.

Study Overview

• Status: Completed
• Conditions: Unilateral Deafness
• Intervention / Treatment: Device: Hearing aid fitting

Detailed Description

Unilateral Hearing Loss (UHL) can be defined as any degree of permanent hearing loss on one ear with normal hearing in the opposite ear. Unilateral hearing loss can be debilitating associated with audiological, psychosocial and educational challenges. Audiological challenges include the reduced ability to localize sounds, reduced awareness on the unaidable side and difficulties hearing in noise or at a distance.

One solution for unaidable UHL is Contralateral Routing of Signals (CROS) and Bilateral Contralateral routing of signals (BiCROS) using a so-called CROS transmitter together with a hearing aid.

The rationale for this clinical investigation is to collect clinical data with a rechargeable CROS transmitter to evaluate the benefits of a BiCROS fitting compared to the alternative treatment option, the monaural hearing aid fitting, and to no treatment in noisy listening situations.

Hearing tests, ear impressions and hearing aid fitting visits are mainly conducted at the National Centre for Audiology in London, Ontario. Those visits are available at the Sonova Innovation Centre Toronto in Mississauga, Ontario, upon request. Outcome measurements are only conducted at the National Centre for Audiology in London, Ontario.

• Study Type: Interventional
• Enrollment (Actual): 22
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • London, Ontario, Canada, N6G 1H1
      • National Centre for Audiology
    • Mississauga, Ontario, Canada, L5L1J3
      • Sonova Innovation Centre Toronto

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 99 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• unaidable hearing loss in worse ear (>N6)
• aidable hearing loss (N3 to N5) on the other ear
• fluent English speaker

Exclusion Criteria:

- aidable hearing loss in both ears

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

5

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: BiCROS fitting with beamformer; Each participant will be fitted with the experimental CROS device on the unaidable ear and with a compatible hearing aid on the other ear. A beamformer (directional microphone) will be enabled during this measurement. Although each ear receives a different device configuration depending on the condition, the participant is assigned as a whole, and assignment is not by ears.	Device: Hearing aid fitting; A participant will wear a hearing aid with and without a CROS device on the unaidable ear.
Experimental: BiCROS fitting omni; Each participant will be fitted with the experimental CROS device on the unaidable ear and with a compatible hearing aid on the other ear. The microphones will be omnidirectional. Although each ear receives a different device configuration depending on the condition, the participant is assigned as a whole, and assignment is not by ears.	Device: Hearing aid fitting; A participant will wear a hearing aid with and without a CROS device on the unaidable ear.
Active Comparator: Monaural hearing aid fitting with beamformer; Each participant will be fitted with a hearing aid on the better hearing ear and no device on the unaidable ear. A beamformer (directional microphone) will be enabled during the measurement. Although each ear receives a different device configuration depending on the condition, the participant is assigned as a whole, and assignment is not by ears.	Device: Hearing aid fitting; A participant will wear a hearing aid with and without a CROS device on the unaidable ear.
Active Comparator: Monaural hearing aid fitting omni; Each participant will be fitted with a hearing aid on the better hearing ear and no device on the unaidable ear. The microphone will be omnidirectional. Although each ear receives a different device configuration depending on the condition, the participant is assigned as a whole, and assignment is not by ears.	Device: Hearing aid fitting; A participant will wear a hearing aid with and without a CROS device on the unaidable ear.
No Intervention: Unaided condition; No intervention, the participants are not fitted with a CROS device and/or hearing aid.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Speech Intelligibility in Noise Measured With US Matrix Test (Noise From a Defined Loudspeaker)	Measuring the Signal to Noise Ratio change in decibels (dB) for speech from the front loudspeaker and noise from the better ear's side with the US matrix Test. Results of the speech test will be the SRT (speech recognition threshold) in dB SNR (signal to noise ratio). The target speaker will be presented from 0° azimuth and is adaptive (start level at 65dB (A)). The noise will be presented on the better ear at an azimuth of 90° or 270° (depending on the site of the better ear), at a level of 65 dB (A).	At the appointment following the 4 weeks home trial each participant went on wearing the BiCROS fitting

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Speech Intelligibility in Noise Measured With US Matrix Test (Diffuse Noise)	Measuring the Signal to Noise Ratio change in decibels (dB) for speech from the front loudspeaker in surrounding noise with the US Matrix Test. Results of the speech test will be the SRT (speech recognition threshold) in dB SNR (signal to noise ratio). The target speaker will be presented from 0° azimuth and is adaptive (start level at 65dB (A). The noise will be presented from a circle of 8 surrounding speakers from 45° to 315° at a level of 65 dB (A) with the participant seated in the centre of the circle.	At the appointment following the 4 weeks home trial each participant went on wearing the BiCROS fitting
Reports of Subjective Quality of Hearing as Assessed by the SSQ	Measured after home trial with the Speech, Spatial and Qualities of Hearing Scale-Benefit (Gatehouse, 2004). The scale ranges from -5 to 5, where negative values indicate that the condition under test is worse than the comparator, 0 indicates no change, and positive values indicate a benefit of the condition under test compared to the comparator.	At the appointment following the 4 weeks home trial each participant went on wearing the BiCROS fitting
Reports of Subjective Quality of Hearing as Assessed by the Bern Benefit Questionnaires	Measured after home trial with the Bern Benefit in Single-Sided Deafness Questionnaire (Komps et al, 2011). The scale ranges from -5 to 5, where negative values indicate that the condition under test is better wihtout the hearing aid, 0 indicates no change, and positive values indicate a benefit with the hearing aid.	At the appointment following the 4 weeks home trial each participant went on wearing the BiCROS fitting
Sound Quality Ratings for Total Impression and Clarity Using Gabriellson et al (1990) Ratings Scales	Ratings of speech in noise presented via loudspeakers using Gabriellson et al (1990) Ratings Scales. Scales include Clarity and Total Impression, and range from 1 to 10. The higher the rating, the better the Clarity and Total Impression.	At the appointment following the 4 weeks home trial each participant went on wearing the BiCROS fitting
Subjective Preference of Hearing Aid Condition	3 alternative forced choice (A, B, no preference or ABX) paradigm with three repetitions for speech in noise presented via loudsepakers	At the appointment following the 4 weeks home trial each participant went on wearing the BiCROS fitting
Listening Effort in Noise Using 7 Point Scale (Holmes et. al., 2018)	Measuring listening effort for speech in multi-talker babble presented via loudspeaker. The scale ranges from 1 to 7, and a higher rating indicates less listening effort.	At the appointment following the 4 weeks home trial each participant went on wearing the BiCROS fitting

Collaborators and Investigators

• Sponsor: Sonova AG
• Collaborators: Western University, Canada
• Investigators: Principal Investigator: Susan Scollie, Western University, Canada

Study record dates

Study Major Dates

• Study Start (Actual): July 11, 2022
• Primary Completion (Actual): March 21, 2023
• Study Completion (Actual): March 21, 2023

Study Registration Dates

• First Submitted: April 8, 2022
• First Submitted That Met QC Criteria: May 12, 2022
• First Posted (Actual): May 18, 2022

Study Record Updates

• Last Update Posted (Actual): June 11, 2025
• Last Update Submitted That Met QC Criteria: June 10, 2025
• Last Verified: March 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Otorhinolaryngologic Diseases; Sensation Disorders; Ear Diseases; Hearing Loss; Hearing Disorders; Deafness; Hearing Loss, Unilateral
• Other Study ID Numbers: 461

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No