Optimizing Soft Speech Recognition in Children With Hearing Loss
Phase: NA
Conditions: Hearing Loss, Sensorineural, Hearing Loss, Bilateral
Sponsor: Sonova AG

 
Study Protocol and Statistical Analysis Plan 
 
 
 
 
 
Optimizing Soft Speech Recognition in 
Children with Hearing Loss (SoftSpeech) 
 
 
Version 3 
 
February 14 2023 
 
 
 
 
 
NCT05299892 
 
 
 
 
 
 

Optimizing Soft Speech Recognition in Children with Hearing Loss 
 
1 
Background    
Children with hearing loss have expressed preferences regarding how their hearing aids function in noise 
and when listening to low-level inputs in quiet environments (Scollie et al., 2010). In general, listening 
comfort is reduced in noise and listening clarity is reduced for low-level conversations or when listening 
at a distance from the talker. Although noise management features and remote microphones can help in 
such situations, management of the full landscape of listening environments is currently beyond the reach 
of these technologies. For example, neither feature provides auditory access to low-level input from 
multiple talkers at a distance, which is problematic given the importance of overhearing for vocabulary 
learning in young children.  
 
A study by Jace Wolfe and colleagues (Wolfe et al., submitted) showed that, even when aided, children 
with hearing loss had significantly poorer speech recognition at 40, 50 and 60 dBA compared to children 
with normal hearing. Furthermore, they showed that increasing hearing aid gain for very low-level inputs 
produced a statistically significant improvement in syllable-final plural recognition and a non-significant 
trend toward better monosyllabic word recognition at very low presentation levels. Additional research is 
needed to document low-level speech recognition ability of children with hearing loss as well as the 
potential benefit or detriment of increasing hearing aid gain for low-level inputs. 
 
A new feature in adult hearing aid technology known as “Speech Enhancer” has been shown improve 
low-level speech perception in adults with hearing loss; however, the effect of Speech Enhancer on 
speech recognition in children is not yet known.   
 
 
2 
Objectives 
The primary objective of this study is to evaluate whether soft speech recognition in quiet is significantly 
improved with Speech Enhancer "on" at the default setting (moderate) compared to Speech Enhancer 
“off” in children with moderate (N3) to severe (N5) hearing loss. 
 
Secondary objectives are to evaluate the potential interaction with comfort in children with moderate to 
severe hearing loss, and to demonstrate that hearing aids compensate for hearing loss in children. 
 
 
3 
Description of the investigational device 
Copy from chapter 3.1 (Intended purpose of the investigational device in the proposed clinical investigation) of 
original CIP. The device name can be replaced by investigational device. 
 
Hearing aids are non-surgical medical devices that enable people with impaired hearing to hear sounds 
again, which could not be heard previously due to a hearing loss.  
The intended purpose of the hearing aid claims a compensation of the hearing impairment, which is a 
recognized disability category, and therefore the hearing aid is considered a medical device. The hearing 
aid is intended to amplify and transmit sound to the ear and thereby compensate for impaired hearing. 
Hearing aids are programmed to the individual hearing loss of an intended person and must therefore only 
be used by this intended person. 
For this study, the intended patient population is children under 18 years of age with hearing loss ranging 
from moderate to severe.   

The study will include the following types of hearing aids: Naída P-PR and Naída P-UP behind-the-ear 
(BTE) devices, and Audéo P-R receiver-in-the-ear (RIC) devices. Although BTEs and RICs are both worn 
behind the ear, their receiver locations differ. In BTE devices the receiver is located in the internal device 
housing whereas with RIC products the receiver is worn in the ear canal.   
 
4 
Design of the clinical investigation 
This confirmatory clinical investigation will be executed at Hearts for Hearing. It is a single-group, single 
blind intervention study with each participant serving as his or her own control. 
However, in certain conditions participant blinding is not feasible (i.e., aided versus unaided 
performance).   
The outcome measures being assessed include: speech recognition in quiet with CNC words and comfort 
ratings using a Multiple Stimuli with Hidden Reference and Anchor (MUSHRA) procedure and looped 
sentences overlaid with low-level transient noise.  
Four different hearing aid conditions will be assessed in this clinical investigation: unaided (no 
amplification), aided with SE “off”, aided with SE “moderate” = 14, aided with SE “strong” = 20.  
• 
Unaided: No treatment, (i.e., no Phonak hearing aids are worn). Unaided condition acts as control 
intervention for intended use. Blinding is not possible for this condition. 
• 
Aided with SE “off”: Aided condition with SE turned “off”. Provides control intervention for intended 
use and baseline for comparison to SE “on” for speech recognition in quiet and preference and comfort 
ratings.  
• 
Aided with SE “moderate”: Aided condition with SE turned “on” at the default moderate setting. Acts 
as the intervention being compared to SE “off” for recognition in quiet and preference and comfort 
ratings. 
• 
 Aided with SE “strong: Aided condition with SE turned “on” at the strong setting. Acts as the 
intervention being compared to SE “off” for speech recognition in quiet and preference and comfort 
ratings. 
Hearing aid program order (speech enhancer settings) will be randomized for all testing conditions except 
for CNC at 50 dBA Quiet with SE Off and unaided CNC in 50 dBA Quiet.  Those conditions are 
administered first to establish candidacy for further aided testing and obtain data for the intended use 
objective. A rand function in excel was utilized to create the randomized list of SE settings for all 
participants for the remaining conditions, which include a second administration of SE Off to minimize 
any changes associated with learning the task.  
Program changes affecting SE strength (i.e., off, moderate, strong) will be initiated via the app by the 
researcher and will be unknown to the participant.  
Study tasks will be completed in the following order, which reflects prioritization of testing related.  
1) Aided CNC Words @ 50 dB HL SE Off 
2) Unaided CNC Words at 50 dB HL 
3) Aided CNC Words 40 and 50 dB HL  
4) Aided subjective comfort ratings  
 
 
 
5 
Risks and benefits of the investigational device and clinical investigation 
 

The risks associated with participating in this study are minimal; study procedures are within the scope of 
practice of the research audiologists and the incidence of adverse events associated with device use is 
low. Moreover, given the short duration nature of the study and exclusive use of hearing aids in the 
laboratory under supervision of qualified research personnel, risks associated with potential long-term 
product insertion, use and maintenance are substantially reduced.  
 
 
6 
Endpoints 
The primary endpoint is percent correct score on the CNC word test. The rationale is that this clinical test 
has been used previously in research by Wolfe and colleagues who showed improved soft speech 
recognition with increased gain for low-level inputs.  
The secondary endpoint is subjective report on a MUSHRA task. It has been used previously to assess 
self-perceived comfort and self-perceived benefit from new features such as Speech Enhancer and can 
give an indication as to whether certain settings (i.e., strengths) are preferred.   
 
7 
Inclusion and Exclusion Criteria 
Subjects fulfilling all of the following inclusion criteria are eligible for the investigation: 
• 
children 4 - 12 years old  
• 
native English speakers with good spoken communication skills 
• 
Healthy outer and middle ear 
• 
capable of achieving aided speech intelligibility scores on open-set CNC word task of > 30% for soft 
speech (i.e., 50 dBA) in quiet 
• 
N3 (moderate), N4 (moderate/ severe) or N5 (severe) bilateral hearing loss 
• 
Experienced full-time hearing aid users (i.e. >5 hours of use per day for 6 or more months) 
The presence of any one of the following exclusion criteria will lead to the exclusion of the subject: 
• 
known allergy to materials in the investigational device 
• 
unable to achieve speech intelligibility scores on an aided open-set CNC word task in quiet with an 
accuracy of 30% of better for soft speech (i.e., 50 dBA) 
• 
Outside the sp;ecified age range or hearing loss range 
 
8 
Measurements and procedures 
Hearing aid programming and laboratory testing will be completed in a single 2.5-hour visit with breaks. 
Test order will begin with CNC word recognition followed by Subjective Comfort/ Preference ratings. 
Aided CNC word recognition in quiet with SE “off” will be completed first because it will determine 
eligibility for further aided testing. Unaided CNC word recognition testing at 50 dB HL will be completed 
next to address the intended use secondary objective even if further aided testing is precluded. Device 
program order (SE condition) will be otherwise randomized and the “SE off” condition will be repeated to 
mitigate any potential reduction in score associated with learning the task on first administration. For all 
tests, program changes will be made by the researcher via the myPhonak or myPhonak Junior app; the 
Speech Enhancer (SE) condition will be unknown to the participant. 
I. 
Device Fitting and Verification  
Children will be fit with study hearing aids matching their personal device form factor; these will be 
programmed and verified according to DSL v. 5 i/o targets. The start-up program will be changed from 
the default (AutoSense OS) to Calm Situation. This program will contain speech enhancer “on” at the 
default (i.e., moderate setting, 14). Two additional programs will be added that are based on “calm”, but 
with Speech Enhancer strength set to “off” and “strong” (i.e., 20). The Speech intelligibility index (SII), a 
score between 0.0 and 1.0, that is highly correlated with intelligibility of speech, will be recorded with SE 
“off”, SE “moderate” and SE “strong”.  
II. 
Speech Recognition  

• 
Stimuli: Speech = CNC words (speech recognition) 
• 
Background:  
o Quiet condition (Ambient noise < 30 dBA) 
▪ 
Presentation Levels: Speech = 40 dBA and 50 dBA; 
• 
Hearing Aid Conditions: SE Moderate (14), SE Strong (20), SE Off; Unaided 
Speech stimuli will be presented from a single speaker located 1m in front of the listener (Figure 1). One 
CNC words list will be presented for each condition with no list repetitions.  
CNC testing will be completed with SE Off, Moderate and Strong in the following conditions: 40 dBA in 
Quiet, 50 dBA in Quiet.  
CNC testing will also be completed unaided at 50 dBA in Quiet.  
III. 
Comfort Ratings  
• 
Stimuli: The speech stimulus is comprised of looped pairs of International Speech Test Signal 
[ISTS] sentences (Holube et al., 2010) overlaid with a low-level transient noise track containing 
sounds such as keyboard typing. 
• 
Background: Quiet (i.e., < 30 dBA ambient room noise) 
• 
Presentation Level: 40 dBA 
• 
HA conditions in randomized order for across participants 
o 
Speech Enhancer On Moderate 
o 
Speech Enhancer On Strong 
o 
Speech Enhancer Off 
• 
Comparisons Conditions: SE Off vs. Moderate; SE Off vs. Strong 
Children will perform listening comfort ratings wearing investigational devices. The stimuli will be 
exclusively presented from a single speaker located 1m in front of the participant. The stimuli are looped 
identical pairs of ISTS sentences overlaid with looped, low-level identical transient noises. Matched 
sentence pairs will be played in immediate succession in different hearing aid conditions: SE “off” versus 
SE “moderate” and SE “off” versus SE “strong”. Participants can request to replay sentence pairs before 
making the following judgments about comfort and preference:   
1) Which sounds better? 
2) Which is more comfortable? 
3) Which do you prefer?  
All analysis of the results will occur at the conclusion of the study. Speech scores and subjective 
questionnaire results will be collected on paper-based forms. Data from these forms will be entered into 
an electronic spreadsheet prior to data analysis. It will be stored in a secure Hearts for Hearing network 
folder and a secure folder on a Sonova Sharepoint site 
 
 
9 
Statistical design and analysis 
 
The primary endpoint variable is the percentage correct score on the consonant-nucleus-consonant (CNC) 
test used to measure speech recognition. Each participant will be evaluated using the CNC test with 
settings of SE on and SE off in the device. A paired t-test  or ANOVA with post hoc comparions will be 

performed with the experiment population using these collected measurements, with an assumed two-
sided Type 1 Error of 2.5%. 
 
The secondary endpoint analysis is comparison of aided versus unaided performance on CNC words. 
 
 
10 
Investigation Duration 
Participant expected duration is approximately 2.5 hours in a one-day appointment. The total expected 
duration of the investigation is 4 months. 
 
11 
Data handling and management 
Case report forms will be completed immediately after the lab visit for each participant.     
The study team will maintain adequate and accurate study records to enable the conduction of the study to 
be fully documented and the study data to be subsequently verified.  Source documents include, but are 
not limited to: CIP, List of Essential Study Documents (LoESD), device records, staff curriculum vitae, 
investigator’s notes, questionnaires, visit dates, randomization lists, SAEs, Adverse events (AEs), etc. 
The documents (physical and electronic) will be kept on file for 5 years.  
During data collection phase of the investigation, physical copies of the data will be compiled and 
digitized/scanned by the researchers and made accessible to the study manager following each study visit. 
Data will be reviewed for mis-entries or inaccuracies on weekly or biweekly basis. 
 
An EDC is not applicable for this investigation.  Data will be entered into a secure Microsoft Excel 
spreadsheet, which is located on secure network drive. Only authorized study personnel will have access 
to the spreadsheet. Only investigators involved in data collection will have authority to enter data. 
 
Participants will be given a participant number to maintain anonymity.   
 
12 
Amendments to the CIP 
The CIP has been amended based on feedback from the PI and key study personnel. After running one 
participant they concluded that the battery was too large to be completed in the 2.5 hour planned time 
frame and that it was very fatiguing for children. Conditions were omitted that were not relevant for study 
claims including removal of the noise condition (which was initially requested by the PI) and omission of 
the UWO Plurals test. The primary study objective, involving speech recognition with and without SE, 
and secondary objective, evaluating hearing aid intended use, were both based on CNC word scores in 
quiet and all those conditions have been retained. The changes do not influence the data required for 
claims and reduce overall burden for participants and their families.  
 
 
13 
Deviations from clinical investigation plan 
Under emergency circumstances, deviations from the CIP to protect the rights, safety and well-being of 
the participants may proceed without prior approval by the Sponsor representative (Study Manager), 
Ethics Commission (EC) and Competent Authority (CA). Such deviations shall be documented and 
reported to the Sponsor within 2 calendar days, and to the EC and CA within the requisite time frame(s) 
described below. Apart from that the investigator is not allowed to deviate from this CIP unless that 
deviation does not influence the investigation data. 
 
14 
Device accountability 
Study devices must be returned at the completion of the study. A device accountability log will be used to 
track the investigational devices used during the clinical investigation.  

Investigators will enter the serial numbers of devices sent from the Sponsor as well as the dates on which 
they were received and returned. 
If an investigational device has to be replaced due to a device deficiency, the investigator will add the 
new serial number, device identifier, date of receiving the replacement, date of return of the defect 
investigational device and mark the returned investigational device as defect on the device accountability 
log. 
In case of device deficiencies, including malfunction, usability issues, or inadequacy in the information 
supplied by the manufacturer including labelling, the devices will be returned to the sponsor for analysis 
and the device will be replaced. 
 
15 
Informed consent process 
Assent and consent will be obtained from participants and parents/ guardians of participants prior to any 
study participation in accordance with WIRB (EC) guidelines.  
For children 6 years of age and younger, no assent is required. Oral assent will be obtained for children 7- 
11 years of age and written assent will be obtained in children 12-17 years of age. In addition, informed 
consent forms will be completed by parents/ guardians of all minor participants. All forms must also be 
signed and dated by the investigator (or their designee) and it will be retained as part of the study records. 
 
16 
Adverse events, adverse device effects and device deficiencies 
Device deficiencies and all adverse events (AE) including all serious adverse events (SAE) are 
collected, fully investigated and documented in the source document and appropriate case report form 
(CRF) during the entire investigation period, i.e. from participant’s informed con-sent until the last 
protocol-specific procedure, including a safety follow-up period (ISO-14155, 2020). Documentation 
includes dates of event, treatment, resolution, assessment of serious-ness and causal relationship to device 
and/or investigation procedure.  
Information on AEs is systematically collected during the regular investigation visits, and phone calls (if 
applicable).  
The investigator(s) will follow-up on a biweekly basis with any participant experiencing an AE until 
either a) the participant reports resolution of the AE or b) 8 weeks have passed since the participant’s final 
visit. If, however, the participant’s condition worsens throughout the 8 week follow-up period, the 
investigator will continue to follow-up biweekly until the AE is resolved or the participant’s condition 
stabilizes over an 8 week period.  
The reporting of Serious Adverse Events and Device Deficiencies follows the Regulation (EU) 2017/745 
and the MDCG 2020-10/1 Safety Reporting in Clinical Investigations of Medical Devices under 
Regulation (EU) 2017/745. 
The causality assessment of the SAE will be conducted according to MDCG 2020-10/1 Safety Reporting 
in Clinical Investigations of Medical Devices under Regulation (EU) 2017/745. 
 
17 
Vulnerable populations 
This investigational study will include minor children from 4 to 17 years of age. 
 
Assent and consent will be obtained from participants and parents/ guardians of participants prior to any 
study participation in accordance with WIRB (EC) guidelines.  
For children 6 years of age and younger, no assent is required. Oral assent will be obtained for children 7- 
11 years of age and written assent will be obtained in children 12-17 years of age. In addition, informed 
consent forms will be completed by parents/ guardians of all minor participants. All forms must also be 
signed and dated by the investigator (or their designee) and it will be retained as part of the study records. 
 
The WIRB has reviewed and approved all consent and assent forms to confirm they are consistent with 
ethics committee requirements. 

 
18  
Suspension or premature termination of the clinical investigation 
The investigation will be suspended or prematurely terminated if the equipment malfunctions or if the 
participants or investigators are exposed to safety risks other than those outlined in this document.  These 
events may include but are not limited to natural disaster, widespread outbreak of illness, compromised 
structure of the investigation site, etc.  
 
The blinding code is kept electronically with the study materials.  This code can be used to link the 
participant with their study ID, if needed.   
This study is planned for a single session.  However, in the event that any participant is asked to return on 
a separate day, the parent or guardian of the participant will be notified regarding the suspension or 
premature termination of the investigation via phone call, e-mail or text.  If the investigation resumes and 
the participant is available to resume the study, they will be scheduled for the lab visit.   
 
19 
Publication policy 
The clinical investigation will be registered in clinicaltrials.gov, a publicly accessible database, as 
required by U.S. regulations.  
The results of the clinical investigation will be published on clinicaltrials.gov no later than one calendar 
year following the final participant appointment.  
 
The results of the clinical investigation will be summarized in a study report and will be submitted for 
publication in a peer-reviewed journal. Partial data will be summarized in a Field Study News. 
The peer-reviewed journal article will be completed by July 2023, but contingent based on reviewing 
timeline of the journal and assuming positive decision acceptance.