Use of Frequency Compression in Severe-profound Hearing Loss Adults

Study Overview
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Brief Summary
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The purpose of this study is to investigate the functional benefits of frequency compression vs no frequency compression or fitted to hearing loss in severe-profound hearing impaired adults with high frequency hearing losses. Thus, assessing whether hearing aids for this patient population can be adapted to improve speech perception.

Detailed Description
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Frequency compression is a feature available on some digital hearing aids, which is aimed at increasing the audibility of high frequency sounds. It works by taking sounds above a fixed start frequency and compresses it into lower frequencies where residual hearing is better.

Official Title
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Do Severe-profound Hearing Impaired Adults Perform Better in Speech Perception With Frequency Compression Switched on or Off or Fitted to Hearing Loss

Conditions
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Frequency Compression, Severe-profound Hearing Impairment

Intervention / Treatment
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* Device: Hearing aid feature: Frequency Compression


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Participants must be over 18 years of age- This study is looking at the use of frequency compression & its effects of speech perception in adults. No ear surgery that would make it impossible to fit a hearing aid- To ensure limited confounding variables. No history of ear surgery within the last 12 months- To ensure limited confounding variables. No history of ear infection(s) within the last 6 months- To ensure no contraindications and limited confounding variables to testing. No otoscopic abnormality making it impossible to fit a hearing aid- To ensure no contraindications to testing. Bilateral severe-profound hearing impairment with air conduction thresholds >71dBHL within the frequency range of 250Hz to 4 kHz- To analyse the effects of frequency compression on speech perception within this patient population. Post lingual deafness, with good spoken English- To ensure reliability of speech testing. Previous bilateral digital hearing aid experience (6+ months)- To ensure limited confounding variables. Written consent required. Exclusion Criteria: Participants under the age of 18 years. History of ear surgery making it impossible to fit a hearing aid. History of ear surgery within the last 12 months.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: FC Deactivated<br>Frequency Compression feature on hearing aids is deactivated for 4 weeks | Device: Hearing aid feature: Frequency Compression<br>* FC Deactivated/Activated & set to default/Activated & set to hearing loss<br>* Other names: Non-linear Frequency Compression;|
| Experimental: FC activated & set to default<br>Frequency compression feature activated on hearing aids and set to default software settings for 4 weeks. | Device: Hearing aid feature: Frequency Compression<br>* FC Deactivated/Activated & set to default/Activated & set to hearing loss<br>* Other names: Non-linear Frequency Compression;|
| Experimental: FC activated and set to hearing loss<br>Frequency Compression feature activated on hearing aids and set to hearing loss cut-off for 4 weeks | Device: Hearing aid feature: Frequency Compression<br>* FC Deactivated/Activated & set to default/Activated & set to hearing loss<br>* Other names: Non-linear Frequency Compression;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| CHEAR Auditory Perception Test | Aided Monosyllabic Speech Test | 4 weeks post hearing aid fitting with adapted hearing aid feature | 
| Adaptive Bamford-Kowal-Bench Test | Aided Sentence Test | 4 weeks post hearing aid fitting with adapted hearing aid feature |