Effects of Remote Microphone Hearing Aids on Classroom Listening, Spatial Listening, and Attention in School-Aged Children With Auditory Processing Disorder
Phase: NA
Conditions: Auditory Processing Disorder
Sponsor: University College, London

                             
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The effects of Remote Microphone Hearing Aids (RMHAs) on classroom listening, 
listening-in-noise and attention skills in children, aged 7-12, with Auditory Processing 
Disorder (APD) 
(Student Study) 
 
 
NCT02353091 
 
 
 
 
 
26/03/20 
 
 
 
The research was funded as a PhD studentship by GN Resound (Company sponsor), which 
also provides the FM systems that will be used in this study, and a UCL Impact award. 
 
 
 

                             
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Summary 
Children with Auditory Processing Disorder (APD) have poor auditory processing skills in the 
presence of normal peripheral hearing. These children are found to have worse listening-in-
noise skills than typically developing peers, while other commonly reported symptoms include 
poor attention and distractibility. One of the management strategies for children with APD is 
the use of Remote Microphone Hearing Aids (RMHAs), which can help improve the signal-
to-noise ratio in the child’s ears. The aim of this randomised control trial was to examine 
whether RMHA use improves classroom listening for children with APD, and to further test 
their effects on children’s listening-in-noise and attention skills following a 6-month 
intervention. 
The principal research question is whether RMHAs improve classroom listening, listening in 
noise performance, listening in spatialised noise and auditory attention, in children with 
Auditory Processing Disorder (APD). We hypothesize that RMHA use will lead to improved 
classroom listening and improved speech-in-noise skills after 6 months of RMHA use. 
Additionally, we hypothesise that listening in spatialised noise and attention skills will remain 
unchanged following the intervention period. 
Twenty-six (26) children with a diagnosis of an APD from the Great Ormond Street Hospital 
Audiology clinic will be recruited. The children need to fulfil the following criteria: 
1. Diagnosis of APD based on routine clinical tests, administered by qualified audiologists, 
and requiring the following conditions: 
2. No neurological or pervasive disorder or developmental delay. Children with a diagnosis 
of Attention Deficit Hyperactivity Disorder, epilepsy, Autism Spectrum Disorder, 
Developmental Language Disorder, Down Syndrome were excluded from the study. 
3. Non-verbal cognitive ability score (IQ) of 85 or more. 
4. Aged between 7-12 years. 
5. Native English speakers. 
6. No prior use of RMHAs. 
 
Background and justification of the study 
Auditory Processing Disorder 
Auditory Processing Disorder (APD) is a disorder where the functions of the ear (outer, middle, 
inner) are normal but the person has difficulty identifying or discriminating sounds (1). For 
children with APD it is particularly difficult to hear when the listening conditions are not ideal. 
For example, when there is background noise it becomes really challenging to focus on the 
speaker. Two other factors that influence their hearing ability are reverberation and the distance 

                             
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from the speaker (2). Some of the most commonly reported symptoms in these children are 
difficulties listening in background noise and inattentiveness, also reflected in findings from 
behavioural tests (3,4). Children with APD perform worse in behavioural tests measuring 
Speech-in-Noise (SiN) skills compared to typically developing children (5,6) and have worse 
performance in sustained auditory attention compared to children suspected of APD but not 
meeting APD diagnostic criteria (7). 
Remote Microphone Hearing Aids 
One of the management strategies recommended to children with APD is the use of Remote 
Microphone Hearing Aids (RMHAs). These are wireless listening devices that pick up the 
speaker’s voice and transmit it to a receiver in the listener’s ear. The use of this system helps 
improve the signal-to-noise ratio for children and bypasses the negative effects of background 
noise and reverberation in the classroom (8,9,2). However, only a handful of studies examined 
the effects of RMHA use on children with APD on specific measures (i.e. SiN, listening in 
noise, language and communication, and memory skills) (9–12).  
Previous research suggests that children with APD after a prolonged use of RMHAs benefit 
from improved speech perception which is possibly linked to an enhanced auditory system (9). 
Adding to that, children with APD have shown improved speech in noise perception when 
using the RMHA, hence emphasizing the advantages of the device in discriminating speech in 
background noise (9,12).  
Attention and ability to listen in spatialised noise in children with APD after the use of an FM 
system has been looked at by one uncontrolled study (12). As the central point of this study 
will be the use of the RMHA by children with APD for 6 months, it is expected that the findings 
could add valuable information on the subject. In addition, possible benefits of the system will 
be examined in detail. More particularly, possible long-term improvements in speech in noise 
performance (unaided), listening in spatialised noise (unaided), and auditory attention 
(unaided) will be examined. 
Listening in noise and attention 
A study compared the scores in the Hearing in Noise test of 10 children with APD at baseline 
unaided and after 5 months of daily RMHA use at school (9). The use of RMHAs during the 
aided test condition at 5 months gave a gain of approximately 10 dB in the SiN test compared 
to the unaided testing at baseline, with the authors concluding that RMHA use improved the 
auditory system in children with APD (9). However, this SiN improvement in the aided 
condition may reflect an auditory acclimatisation benefit similar to the one reported for hearing 
aids (13), as there was no significant improvement between pre- and post-intervention in 
unaided SiN testing. Another APD study used low-gain hearing aids equipped with a 
directional microphone and noise reduction (14), to examine changes in aided SiN skills in 14 

                             
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children with APD. They reported improved aided SiN test results1 after 6 months of RMHA 
use. Another intervention trial examined the ability to listen in spatial noise2 on 28 children 
with APD who used RMHAs for 5 months (12). Children were tested on two tasks, easy words 
and hard words, and two conditions, with and without the RMHA at baseline and post-
intervention. Results showed a significant improvement only in the easy words task when 
comparing the unaided with the aided conditions (12). All three trials lacked control groups 
and randomised designs, thus further validation in controlled trials, especially in unaided 
conditions, is required. 
Furthermore, to date only one study looked into the long-term impact of RMHAs on 
behavioural attention tests in children with APD. Specifically, sustained auditory and sustained 
visual attention was examined in 28 children with APD after a 5-month RMHA intervention, 
without showing any significant change over the intervention period (12). One other study used 
the Children’s Auditory Performance Scale questionnaire, completed by parents at baseline 
and after 6 months of using the directional microphone hearing aids at school (14). While the 
Auditory Attention Span subscale of the questionnaire showed significantly improved scores 
post-intervention, it still remained below what was considered normal cut-off. Parents observed 
their children at home, when hearing aids were not used, suggesting that the improvement in 
the subscale scores may have been due to lasting effects on their attentive behaviours. The 
findings from these two studies are conflicting, but none of the trials used a randomised control 
design (14). 
Aim and hypotheses 
In the present study we aim to test the impact of long-term RMHA use on self-reported 
listening, behavioural SiN performance and to assess behaviourally whether listening-in-
spatialised-noise skills change after prolonged RMHA use and to assess the impact RMHA use 
has on attention skills. 
Research questions:  
The principal research question was to examine the effects of RMHAs on classroom listening, 
listening in noise performance, and auditory attention in children with APD. 
Hypotheses: 
i. 
Children with APD who use RMHAs will show greater improvements in classroom 
listening, listening in noise and sustained auditory attention (unaided) after 6 months of 
RMHA use in comparison to the APD control group. 
 
1 The North Western University word-list was used in combination with speech-shaped noise coming from 180o 
that was individually adjusted (14). 
2 Words from the Lexical Neighbourhood Test were presented from the front, while a 100-talker babble recording 
was presented left, right, and behind the subject (12). 

                             
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ii. 
Children with APD who use the RMHA will not show greater improvements in listening 
in spatialised speech noise and divided and visual attention measures after 6 months of 
RMHA use in comparison to the APD control group. 
 
Summary of main issues 
Research suggests that children with APD after a prolonged use of RMHAs benefit from 
improved speech perception which is possibly linked to an enhanced auditory system (9). 
Adding to that, children with APD have shown improved speech in noise perception when 
using RMHAs (in an uncontrolled study); hence emphasizing the advantages of RMHAs in 
discriminating speech in background noise (9). There are not many studies, though, that focus 
on the use of RMHAs on children with APD.  
This study will assess the effects of RMHA use on a range of outcome measures. As the central 
point of this study will be the use of RMHAs by children with APD for 6 months, it is expected 
that the findings could add valuable information on the matter. In addition, possible benefits of 
RMHAs will be examined in detail. More particularly, possible improvements in auditory 
attention, listening in spatialised noise and speech in noise discrimination (unaided) will be 
looked into. 
Intervention ethical issues: 
We will split the children with APD into (a) children who will only receive the RMHA, (b) 
children who will not receive any intervention for the study period (this group will receive the 
RMHA after we complete the study, at 6 months under this conditions: The recommendations 
by the APD clinic at GOSH include RMHA use as management strategies. 
Currently from an audit conducted at GOSH APD Clinic, only 1 in 3 children who are 
recommended to have a RMHA obtain this by school funding (or by their parents funding the 
device) and this takes place several months after the recommendation has been made. 
Therefore, provision of this device is not standard practice. As such RMHAs are issued as part 
of this research study under the condition mentioned above. 
An inclusion of a control, no intervention group, is essential for the Randomised Control Trial 
design we follow.  
School and teacher involvement: 
The teachers of the children who receive the FM systems will be provided with an information 
sheet and consent form and will be required to wear the microphone (which picks up the 
teacher's voice and transmits it wirelessly to the ear receivers in the child's ear) for the duration 
of the class. Remote microphone hearing aids are provided (funded by the school budget) to 
some children after clinical recommendations and this is not an unusual situation within the 
school environment. 

                             
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We will liaise with the teacher as well as the Special Educational Needs Co-ordinator (SENCO) 
of the school in order to ensure that the school will be aware that the student has been issued 
with the RMHA. A general guide for the system will be made available in addition to 
information conveyed by the Research Fellow (PhD student) who will visit the school once per 
term. 
Informed consent:  
The child’s parents will be given detailed written information and consent forms to sign about 
taking part in the study. They will be given up to a week to study and decide whether they wish 
for their child to participate in the study. They will only be allowed to take part once they have 
understood the purpose and procedures of the study and they have signed the consent forms. 
In addition, children will also be given information sheets adjusted to their age. Written assent 
from the children in the presence of their parents or carers will be sought.  
Rights to withdraw from the study: 
This will be outlined on both the information sheet and consent form and explained verbally 
throughout. This information will state that participants will be allowed to withdraw from the 
study at any point should they wish to do so. Withdrawal from the study will not involve any 
penalty or loss of benefit to them –this information is clearly underlined at the information 
sheet and will be made clear to them verbally. 
Data protection:  
The parents of the participant and the participant will be informed that their information will 
be anonymised and kept confidential. Data will be anonymised prior to analysis by the use of 
participant codes. Storage of the data will be within a secure password protected database and 
locked filing unit within UCL, in accordance with the data protection act 1998. If withdrawals 
take place the participants’ data will be deleted. 
 
Research Design and Methodology 
Participants and Recruitment 
We will recruit 26 children, 7-12 years old. All children will have been diagnosed and referred 
from the Auditory Processing Disorders Clinic at Great Ormond Street Hospital. The total 
sample size is decided using this power sample: N = 24 (total sample size) calculated using the 
F test for repeated measures between-within interaction Analysis of Variance (ANOVA) based 
on an estimated 0.5 effect size f(U), 80% power, at 5% significance, using 2 groups and 3 
measurement points. To account for a 10% loss due to follow-up, the total sample size of this 
study was 26 children, aged 7-12.   
Inclusion criteria: 
1. Diagnosis of APD based on routine clinical tests, administered by qualified audiologists, 
and requiring the following conditions: 

                             
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a) Reported parental SiN and other reported listening difficulties. 
b) Normal peripheral hearing and middle ear function; i.e. air conduction PTA below 20 
dB in all octave frequencies between 250 Hz and 8 KHz (31), middle-ear pressure 
between -150 to +50 daPa, middle-ear admittance between 0.3 to 1.6 cm3 and ear-canal 
volumes between 0.4 to 1.0 cm3 (32). 
c) Abnormal performance on the Auditory Figure Ground (AFG) SiN test of the SCAN-3 
C (i.e. at the 1st percentile score as per UK norms), and 
d) Abnormal performance (-2 SDs from the normative mean) on at least one auditory 
processing test (i.e. Frequency Pattern Test [FPT], Dichotic Digits Test [DDT], 
duration pattern test, Gaps-in-Noise [GiN] or random gap detection pattern tests), or a 
score of -3 SDs from the normative mean on only one auditory processing test (any test 
from conditions ‘c’ and ‘d’), and/ or abnormal performance (-2 SDs from the mean) on 
the Spatial Advantage and Total Advantage/ High-cue Speech Reception Threshold 
(SRT) subtests of the Listening in Spatialised Noise – Sentences (LiSN-S) test. 
2. No neurological or pervasive disorder or developmental delay. Children with a diagnosis 
of Attention Deficit Hyperactivity Disorder, epilepsy, Autism Spectrum Disorder, 
Developmental Language Disorder, Down Syndrome were excluded from the study. 
3. Non-verbal cognitive ability score (IQ) of 85 or more. 
4. Aged between 7-12 years. 
5. Native English speakers. 
6. No prior use of RMHAs. 
Subjects will be semi-randomly assigned to each of two intervention arms. The two groups will 
be stratified for age and balanced for sex. 
Children will be given RMHAs to use at school and will be compared to the control (no 
intervention) group. Children will be enrolled in the study for 6 months. All groups will be 
tested before the start of the RMHA intervention, after 3 months, and at the end of the study 
(after 6 months of use of the interventions). 
Following are the assessments to be performed for both groups at UCL Ear Institute (detailed 
explanation of these tests is given later): 
• Baseline (before recruitment, 0 months into the study): 
o Pure Audiometry Test (PTA)  
o Non-verbal IQ test (Weschler test of Non-verbal intelligence) 
o Children Questionnaires (LIFE-R) 
o Attention test (TEACh) 
o Listening in Spatialised noise (LiSN-S) 
o Questionnaires (CHAPS, CCC-2) 
• At 3 months 

                             
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o Children Questionnaires (LIFE-R) 
o Attention test (TEACh) 
o Listening in Spatialised noise (LiSN-S) 
o Questionnaires (CHAPS, CCC-2) 
• At the end of the study (6 months later): 
o Children Questionnaires (LIFE-R) 
o Attention test (TEACh) 
o Listening in Spatialised noise (LiSN-S) 
o Questionnaires (CHAPS, CCC-2) 
 
Explanation of each test: 
1. A hearing test (Pure Tone Audiometry approx. 10mins). To determine their hearing is 
normal. 
2. Non-verbal IQ test (Weschler test of non-verbal intelligence). To be performed by the PhD 
Student. (approx. 15mins). To assess determine whether their intelligence level is above 
normal.  
3. Listening in spatialised noise test (LiSN-S, approx. 15mins). To be administered through 
the use of headphones by the PhD student. To determine their listening in spatialised speech 
noise abilities.  
4. An attention test. The Test of Everyday Attention for Children (TEACh). To be conducted 
as play type activities by the  PhD student after receiving sufficient training by the clinical 
psychologist. (approx. 45mins possibly cut down to 30mins). To assess their attention. 
5. Two questionnaires to be filled by the children’s parents.  
a. The Children’s Communication Checklist-2 (CCC-2). A 70-item questionnaire 
which screens for communication problems (including language disorders and 
autism).  
b. The Children’s Auditory Performance Scale (CHAPS). It assesses aspects of 
children’s listening.  
6. One questionnaire to be completed by the children (Listening Inventory For Education-
Revised [LIFE-R] for assessing their listening difficulty.  
Data analysis: 
Data were analysed in SPSS 22 statistics software, using a mixed ANOVA, with group  as the 
between-subjects factor with two levels (i.e. control or RMHA) and time the within-subjects 
factor with three levels (i.e. baseline, 3, and 6 months) . 

                             
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Other issues: 
None of these tests are invasive or unpleasant, and they are conducted in comfortable sound 
levels (slightly higher than the usual conversational level). Any additional information on the 
children that might emerge during the study will be reported back to the clinician at the APD 
clinic to inform the child’s management.  
All children who participate will receive a book voucher of £10 at the end of each test session. 
Travel expenses will also be reimbursed (up to £10).  
 
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