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Trial registered on ANZCTR


Registration number
ACTRN12617000898358
Ethics application status
Approved
Date submitted
16/03/2017
Date registered
19/06/2017
Date last updated
6/06/2018
Type of registration
Retrospectively registered

Titles & IDs
Public title
Effect of a sound processor on listening effort in Cochlear Implantees
Scientific title
Effect of a sound processor (noise reduction algorithm) on listening effort and its relationships with cognitive capacity in experienced adult cochlear implant (CI) users
Secondary ID [1] 291268 0
Nil Known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Deafness 302208 0
Condition category
Condition code
Ear 301813 301813 0 0
Deafness

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Design Overview
Cochlear implant recipients aged greater than 18 years will be asked to participate. A single-subject research design (in which each subject serves as his or her own control) is appropriate since it accommodates the heterogeneity that characterizes hearing-impaired populations.
The study will use a prospective, sequential enrolment, within-subject design where each subject is his/her own control (repeated-measures). The noise reduction algorithm will be randomly programmed to the sound processor CP1000 in Program 1 or Program 2 by the cochlear implant audiologist. The participant and the investigator conducting the assessment will be blinded to the program allocation

Visit One: will take place at participant’s primary programming centre, the University of Auckland Clinics. During this visit the participant will sign the consent form. The participant’s audiologist will provide the Cochlear N7 device (which will be used continuously throughout the 8 weeks of the study) and convert the participant’s CP900 to the CP1000 sound processor programs with the recipient and will randomize the noise reduction algorithm into Program 1 or Program 2 (noise reduction system is designed to attenuate background noise levels in each channel while retaining speech information). Both programs are activated throughout the 8 weeks of the study and the participants are encouraged to select both programs for listening in everyday life using their remote control so that the participant gains listening experience with both programs before being tested. During testing sessions the researcher will select the program to be evaluated one at a time. Participants will be instructed to use both programs (Cochlear N7 device) during the acclimatization period (period of time where there is an improvement of speech perception due to auditory processing changes) but they will not be told which program has the noise reduction, If any problems arise with the device they will still have their own usual device. Visit 2 will be scheduled 2 weeks after Visit 1 at a time convenient for the participant.

Visit two: Participants will complete different assessments as described below using the Cochlear N7 device. Cognition is tested at the beginning in visit two only, with the participant wearing their hearing devices set to their preferred settings. After the cognition test the single and dual tasks will be completed with each program activated in turn, in counterbalanced order. During this visit participants will complete a hearing quality questionnaire (SSQ-C) regarding their self-perception of difficulty in various everyday situations. Participants will be scheduled for the third and last session in 2 weeks’ time.

Visit three (two weeks after visit 2): During this session participants will be asked to repeat the same assessments and questionnaires as visit 2 (for both programmes). They will also be interviewed briefly to find out how they found the trial and the assessments. After the assessment, the primary audiologist will return to the primary programming using the participant’s current device. Participants will return the Cochlear N7 device and all the parts provided.

CI programming and testing will conducted by a senior CI Implant rehabilitationist and audiologist respectively. Each session will have a duration of 2 hrs approximately. Adherence to the use of the device will be measured by checking on the datalog (software function) for example how many hours per day they are wearing the processor and which sound environments they have been in. This information will be obtained by the CI implant rehabilitationist.

Evaluation Materials and Test Conditions
Cognition assessment

WAIS-IV Digit Span: The Digit Span test includes three different digit span tasks (Forward, Backward, and Sequencing). Forward digit span requires the participant to recall number sequences in the same order as they are presented. Backward digit span requires the participant to repeat the number sequences in reverse order. For the sequencing task, participants are instructed to order the presented number sequence from highest to lowest number.
Reading Span test: Reading span is a Working Memory test designed to tax memory storage and processing simultaneously. The original reading span test was introduced by Daneman and Carpenter (1980).
The participant’s task is to comprehend sentences and to recall either the first or the final words of a presented sequence of sentences. The percentage score of correctly recalled words out of the total number of presented words determines the performance measure.
Duration: 15 minutes approximately

Prior to data collection during visits two and three, practice will be provided for each task described below until the participant is familiar with the task and has understood the instructions clearly (this will take about 30 minutes in total).
Single Task paradigm

Speech recognition in noise (Primary task)
The primary task will be a sentence-in-noise task presented at a fixed overall speech performance level of 50% correct performance (50% SRT) using the adaptive Australian Sentence Test in Noise (AuSTIN) sentences (Dawson, Hersbach, & Swanson, 2013). Participants are instructed to repeat back the sentences presented from a loudspeaker (single spatial configuration with the signal and noise at 0°; front). Thirty sentences will be used to obtain the 50% speech recognition threshold (SRT) scores.
The verbal response times to auditory stimuli (VRT) will be obtained, which is calculated from the offset of the stimulus, as logged by the experimental program, to the onset of the verbal response (Pals, Sarampalis, van Rijn, & Baskent, 2015).
Two measures will be obtained using both CI programs
Duration: 10 minutes in total approximately (using both programs)

Visual reaction time (Secondary task)
The visual task was developed based on Sternberg’s (1966) short-term-memory-scanning paradigm. Stimulus presentation and response recording is run on a 17 inch laptop using Inquisit 4 software. Participants are presented with a series of digits (one to six digits long) in white on a black background. Following this the participants are prompted with a target digit (yellow on a black background) and are required to indicate if it was either part of the series or not, using one of two keys on the keyboard. The software calculates reaction time (RT) and accuracy for each response. Each block consisted of 18 trials.
paradigm. RTs are displayed on the computer monitor after each trial. Two baseline measures will be obtained, using both CI programs.
Duration: 10 minutes in total approximately (using both programs)

Dual Task-paradigm

After primary- and secondary- single task measures are obtained, the dual-task paradigm will be administered to participants. In the dual task, participants are told that their main task is to repeat the sentences, but they should do the visual task as best they can at the same time. Measures are obtained using both programs.
After each dual-task assessment participants complete questionnaires examining listening effort
Participants repeat the Secondary visual task at the end of the dual task paradigm test-session to verify that performance is not affected by learning or fatigue.
Duration: 10 minutes in total approximately (using both programs)

General comments
The total duration of the study for the participant will be no more than 8 weeks. The participants will be required to visit their cochlear implant clinic at the University of Auckland three times as part of the study. Recruitment will be through advertisements at The University of Auckland Hearing Clinic.
At Visit 1 the participant will be screened and consented and thus enrolled into the study. At this time the participants will be given 2 programmes in the investigation Cochlear N7 device. The participants will be asked to keep diary notes of anything they notice about program 1 and program 2 during the 2-week period between visit 1 and visit 2
Visit 2 will occur approximately 2 weeks after visit 1. At Visit 2 the participant will complete the study assessments: subjective questionnaires, speech testing (primary task), visual reaction test (secondary task) and dual-task paradigm.
Visit 3 will occur approximately 2 weeks after visit 2. The same tests will be administered as visit 2.
Intervention code [1] 297332 0
Rehabilitation
Intervention code [2] 297333 0
Treatment: Devices
Comparator / control treatment
No noise reduction algorithm (OFF) will be considerate the standard
Control group
Active

Outcomes
Primary outcome [1] 301418 0
Speech in noise scores (SRT dB) measured by AusTIN test for noise reduction ON condition
Timepoint [1] 301418 0
Visit 2 and visit 3 (conducted two weeks apart).
Primary outcome [2] 302469 0
Speech in noise scores (SRT dB) measured by AusTIN test for noise reduction OFF condition
Timepoint [2] 302469 0
Visit 2 and visit 3 (conducted two weeks apart).
Secondary outcome [1] 332568 0
Mean reaction time scores for the dual task-paradigm for noise reduction ON condition for the Sternberg’s visual task
Timepoint [1] 332568 0
Visit 2 and Visit 3 (Conducted 2 weeks apart).
Secondary outcome [2] 335056 0
Mean reaction time scores for the dual task-paradigm for noise reduction OFF condition for the Sternberg’s visual task
Timepoint [2] 335056 0
Visit 2 and Visit 3 (Conducted 2 weeks apart).
Secondary outcome [3] 336097 0
Mean accuracy scores for the dual task-paradigm for noise reduction ON condition for the Sternberg’s visual task
Timepoint [3] 336097 0
Visit 2 and Visit 3 (Conducted 2 weeks apart).
Secondary outcome [4] 336098 0
Mean accuracy scores for the dual task-paradigm for noise reduction OFF condition for the Sternberg’s visual task
Timepoint [4] 336098 0
Visit 2 and Visit 3 (Conducted 2 weeks apart).
Secondary outcome [5] 336099 0
Mean scores for self-perception of difficulties measured by SSQ-C, questionnaire
Timepoint [5] 336099 0
Visit 2 and Visit 3 (Conducted 2 weeks apart).
Secondary outcome [6] 336100 0
Mean scores for self-perception of difficulties measured by RSME questionnaire for the dual task-paradigm
Timepoint [6] 336100 0
Visit 2 and Visit 3 (Conducted 2 weeks apart).
Secondary outcome [7] 336101 0
Mean scores for self-perception of difficulties measured by NASA-TLX questionnaire for the dual task-paradigm
Timepoint [7] 336101 0
Visit 2 and Visit 3 (Conducted 2 weeks apart).
Secondary outcome [8] 336102 0
Percentage scores for reading span test
Timepoint [8] 336102 0
Visit 2
Secondary outcome [9] 336103 0
Composite scores for digits span test
Timepoint [9] 336103 0
Visit 2

Eligibility
Key inclusion criteria
1.- > 50% speech perception scores for CNC (consonant-nucleus-consonant) words presented in quiet
2.- Individuals aged greater than 18 years that are native English speakers and are capable of completing the study evaluation as deemed by their primary audiologist
3.- Unilateral or bilateral cochlear implant recipients of an approved Nucleus Cochlear Implant.
4.- A minimum of 12 months’ experience with a CP800 or CP900 series sound processor, and current MAP programmed within 6 months prior to Visit 1
5.- Willingness to participate in and to comply with all requirements of the protocol
6.- Able to demonstrate protocol competence as confirmed by primary audiologist
Minimum age
18 Years
Maximum age
No limit
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
1.- Unrealistic expectations on the part of the subject, regarding the possible benefits and risks
2.- Unwillingness or inability of the candidate to comply with all investigational requirements
3.- Additional difficulties (such as visual impairment) that would prevent or restrict participation in the audiological evaluations

Study design
Purpose of the study
Treatment
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s

The people assessing the outcomes
Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint(s)
Efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment outside Australia
Country [1] 8725 0
New Zealand
State/province [1] 8725 0

Funding & Sponsors
Funding source category [1] 295725 0
University
Name [1] 295725 0
The University of Auckland
Address [1] 295725 0
Speech Science
Tamaki Campus, Bld 721, L3
261 Morrin rd
St Johns
Auckland 1072
New Zealand
Country [1] 295725 0
New Zealand
Primary sponsor type
University
Name
The University of Auckland
Address
Speech Science
Tamaki Campus, Bld 721, L3
261 Morrin rd
St Johns
Auckland 1072
New Zealand
Country
New Zealand
Secondary sponsor category [1] 294845 0
None
Name [1] 294845 0
Address [1] 294845 0
Country [1] 294845 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 297028 0
Health and Disability Ethics Committees
Ethics committee address [1] 297028 0
Ministry of Health
133 Molesworth Street
PO Box 5013
Wellington
6011
Ethics committee country [1] 297028 0
New Zealand
Date submitted for ethics approval [1] 297028 0
08/02/2017
Approval date [1] 297028 0
22/03/2017
Ethics approval number [1] 297028 0
17/CEN/37

Summary
Brief summary
This study evaluates the effect of a sound processor (noise reduction algorithm) on listening effort and its relationships with cognitive capacity in experienced adult cochlear implant users

.Hypothesis

1.- The noise reduction algorithm decreases the listening effort experienced by CI users when they are listening to speech in noise and doing a secondary task.
2.- Working memory capacity is associated with measures of listening effort.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 72758 0
Prof Suzanne Purdy
Address 72758 0
Prof Suzanne Purdy
261 Morrin Road, Tamaki Campus
Bldg 721-319, Speech Science
ST JOHNS
AUCKLAND 1072
The University of Auckland
Country 72758 0
New Zealand
Phone 72758 0
+64 9 923 2073
Fax 72758 0
Email 72758 0
sc.purdy@auckland.ac.nz
Contact person for public queries
Name 72759 0
Dr Oscar Canete
Address 72759 0
Dr Oscar Canete
261 Morrin Road, Tamaki Campus
Bldg 721-304, Speech Science
ST JOHNS
AUCKLAND 1072
The University of Auckland
Country 72759 0
New Zealand
Phone 72759 0
+64 9 373 7999
Fax 72759 0
Email 72759 0
ocan093@aucklanduni.ac.nz
Contact person for scientific queries
Name 72760 0
Dr Oscar Canete
Address 72760 0
Dr Oscar Canete
261 Morrin Road, Tamaki Campus
Bldg 721-304, Speech Science
ST JOHNS
AUCKLAND 1072
The University of Auckland
Country 72760 0
New Zealand
Phone 72760 0
+64 9 373 7999
Fax 72760 0
Email 72760 0
ocan093@aucklanduni.ac.nz

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary