Get documents about "Children with Mild and Unilateral Hearing Impairment
Document Sample
EDHI Feb 2004
Children with Mild and
Unilateral Hearing
Impairment
Current management and
outcome measures
Kirsti Reeve Ph.D.
Developmental Disabilities Institute
Wayne State University, Detroit MI
Overview
Current management for children with mild
and unilateral hearing impairment (HI)
Outcome measures:
Speech and language
Cognition
Why these populations?
Very little known about management or
outcomes for mild or unilateral HI
NHSP offers the potential for early
identification
There is strong evidence that early
identification gives improved outcomes in
moderate and greater HI populations
Need to ascertain whether it would be
appropriate for these groups
Study overview
Two separate studies
Questionnaire survey to audiologists
investigating management options
Outcomes study
Obtained epidemiological data
Assessed impact of HI quality of life
Assessed impact of HI on speech, language &
cognition
Current management:
options for children with mild or
unilateral hearing impairment
Why assess service provision?
Areas of uncertainty
Numbers of children being identified
Age of identification
Management options for these groups
Level at which to provide hearing aids
How was it done?
Single page questionnaire survey
Sent out to 131 professionals
throughout the UK
1 reminder
56 responses (43%)
Results
Information on the mild and unilateral
cases seen
Management offered to those cases
Results
Information on the mild and unilateral
cases seen
Management offered to those cases
Numbers of children with
bilateral mild impairment
Defined as 20-40dBHL permanent
sensorineural loss
Comprise 8% of total caseload
Range seen from 0 to 300 (mean of 25)
Estimated total number seen by 56
clinicians: 1220
Numbers of children with
unilateral hearing impairment
Defined as permanent sensorineural
loss in one ear only.
Comprise 4% of total caseload
Range seen from 0 to 40 (mean of 9)
Estimated total number seen by 56
clinicians: 443
Numbers of children seen
N
25
Mild
Unilateral
20
15
10
5
0
0 1-5 6-10 11-15 16-20 21-25 26-30 31-35 36+
Numbers
Numbers found
Literature estimates prevalence figures at:
between 0.5-5.2% for unilateral impairment
Between 1 and 5.4% for mild impairment
“It is well recognized that an inverse relationship
exists between the prevalence and degree of
hearing loss” – Bess 1984
The low percentage as ascertained by this
questionnaire would imply that large numbers of
these populations are not receiving audiological
management
Age of Referral
N
35
Mild
30 Unilateral
25
20
15
10
5
0
0-6 months 6-12 months 1-3 years 4-6 years 6 years +
Age
Age of referral, data from Trent Region
(Mild n=50, Unilateral = 30)
percentiles
100
90 X
80
X
70
X
60 X
50 X
40 X
Moderate
All Trent
30
, Mild
20
, X Unilateral
10
,
0
,
'
)
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140
Age in months
Age of referral
Age of referral is late for both groups of
children when compared with Trent data
Children with unilateral impairment
identified significantly later than children
with mild impairment
Modal age of between 4 and 6 years
suggests that the school entry is a factor
leading to identification
Results
Information on the mild and unilateral
cases seen
Management offered to those cases
Management
Unilateral
None/Discharge
Mild
Speech Therapy
Review
Options
Refer
Advice
Aid
0 10 20 30 40 50
Frequency
Management
Most frequent options are review and
advice
Children with mild HI are significantly more
likely to be offered:
Hearing Aids (p=0.0005)
Speech Therapy (p=0.003)
Referral to other professional (p=0.022)
Provision of aids
Uncertainty among professionals on
whether to aid mild HI
Level below which you would not consider
providing aids:
25dBHL (range from 15 - 35dBHL)
Level above which you would definitely
provide aids:
40dBHL (range from 25 to 50dbHL)
Management conclusions
Mild and unilateral HI are under-
represented in the caseload of this sample
These groups of children are identified
later than children with more severe
impairments
Management is still uncertain whether to
provide aids and at what level for children
with a bilateral mild impairment
Outcome Measures –
Language and Cognition
Hypotheses
Language is likely to be affected to some
degree by a mild or unilateral hearing
impairment
There will be a positive relationship
between language scores, non-word
repetition and verbal reasoning
Subjects
41 children from CHAC met study criteria:
Aged 6-11
Bilateral mild, or unilateral hearing impairment
HI is sensorineural
No associated syndromes, or other problems.
No known learning or cognitive disabilities.
English as first language
20 children agreed to participate though one
child DNA’d twice, and was not followed up a
third time.
Participants
8 mild
11 unilateral
6 mild, 3 moderate, 1 severe, 1 profound
5 left ear impaired, 6 right ear
5 girls, 14 boys
Aged 6-11, average age 8yrs 3 months
Age of identification ranged from 9 months to 6
years 7 months (mean of 2 years 4 months)
Assessments
The session consisted of:
Computer based test of sound lateralization
Standardised language assessment (CELF-3
UK)
Children’s test of Non word Repetition
BAS verbal & non-verbal reasoning (IQ)
Most sessions lasted 90-120 mins
including breaks.
Results
Language
Non-word repetition
Cognition
Results
Language
Non-word repetition
Cognition
Language testing - CELF 3 UK
Standardised on UK population
Six subtests:
3 for receptive language (understanding)
Sentence Structure (aged 6-8) / Semantic
Relationships (aged 9+)
Concepts and Directions
Word Classes
3 for expressive language (speaking)
Word Structure (6-8) / Sentence Assembly (9+)
Formulated Sentences
Recalling Sentences
Means of all language scores
Standardised Test: mean:100, sd:15
110
Receptive Language
Mean: 89.65,
sd 13.18
100
Expressive Language
Mean: 85.76,
sd 13.51
90
Total Language
Mean: 86.29,
sd 14.01
80
95% CI
70
N= 17 17 17
Receptive language s Total language score
Expressive language
Total Language Scores for
individual subjects
120
110
100
90
80
70
60
Unilateral HI Mild HI
.5 1.0 1.5 2.0 2.5
type of hearing i mpai rment
Speech & language results 1
Unilateral group - total language score
mean of 91.78
Mild group - total language score mean of
80.12
With a linear regression, the difference in
scores just misses significance (.089) -
this could be due to the small sample size.
Speech & language results 2
Converting scores to age equivalent gives
an average language delays of:
6 months for children with a unilateral
impairment
24 months for children with a mild impairment
Results
Language
Non-word repetition
Cognition
Children’s Test of Non-word
Repetition
Assesses phonological memory, and is
predicative of literacy development
Administered via computer
Scores converted to standard scores,
with a mean of 100, sd of 10
CN-Rep Results 1
Both groups of children scored below
100 on this task
Children with mild HI: mean= 87.75
Children with unilateral HI: mean=95.55
CN-Rep results by type of hearing
impairment
110
100
90
80
70
N= 11 8
unilateral bilateral
type of hearing impairment
CN-Rep results 2
Significant correlation of .953 with the
recalling sentence CELF subtest (p=0.005)
controlling for age
Scores can be compared with those from
an OME group and hearing controls from
BOS study
CN-Rep scores as a function of type of
hearing impairment
115 110.7
110
105.2
105
standard score
100
95.6
95
90 87.8
85
80
75
70
None OME Unilateral Mild
type of hearing impairment
Results
Language
Non-word repetition
Cognition
Cognition
Two tests from the British Abilities Scale
(BAS)
Similarities (verbal reasoning)
Why do these things go together:
“milk, lemonade, coffee” , “cod, shark, pilchard”
Need to produce the superordinate
Matrices (non verbal reasoning)
Finish the pattern
Cognition results 1
Similarities (verbal reasoning)
centile
scores ranged from 17-84
mean of 45.71, sd 20
Matrices (non verbal reasoning)
centile
scores ranged from 29-99
mean of 77.82, sd of 23.55
So - significantly impaired scores on verbal
reasoning (p<.001 on independent samples t-
test)
Cognition results 2
Only 3 children, all with mild HI, had higher
verbal than non-verbal reasoning
Mean difference of 32 centiles between
verbal and non-verbal scores
Significant difference in non-verbal score
depending on type of HI
Independent samples t test gives p=0.027
Cognition results
100
80
60
40
Similarities centile
95% CI
20 matrices centile
N= 9 9 8 8
unilateral bilateral
type of hearing impairment
Cognition results 4
Correlation of .625 between verbal
reasoning and CELF language scores
(p=0.003)
Results can be compared across severity
range with outcomes data from larger
studies
Reasoning scores as a function of type
of hearing impairment
70
Verbal
60
50
t-score
40
30
20
10
0
No
O
Un
M
Se
M
Pr
M
ild
od
of
ve
n
ila
E
e
ou
er
t
re
er
at
nd
al
e
Reasoning scores as a function of type
of hearing impairment
70
Verbal
60
50
t-score
40
30
20
10
0
No
O
Un
M
Se
M
Pr
M
ild
od
of
ve
n
ila
E
e
ou
er
t
re
er
at
nd
al
e
Outcome measures conclusions
The caveat -
These children were all identified through
CHAC. Therefore they have made it to the
attention of the audiology services
There may be ascertainment bias which
could effect the results and make
generalisation more difficult
Outcome measures conclusions
Laterality of impairment for the unilateral
group was not predictive of performance
Greater severity of impairment was
correlated with better performance on
language outcomes ...
… although numbers are very small
Outcome measures conclusions
Children with mild or unilateral hearing HI who
are known to audiology services could be at risk
for developing language problems
Children with a bilateral mild impairment are
perhaps at greater risk than those with a
unilateral impairment, regardless of severity
Overall conclusions
Children with mild impairments are
showing language deficits that may
possibly be ameliorated through earlier
identification
There is a need for further research in the
area of amplification provision for mild
impairments
Overall conclusions
Children with unilateral impairments
showed a variable performance which was
not correlated with severity of impairment
or side of impairment
There is the need for a larger study to
investigate these findings further
Early identification through NHSP is still
recommended
Thanks to
Adrian Davis and Sally Hind at MRC
Institute of Hearing Research, Nottingham
Paul Shaw and the staff at CHAC,
Nottingham
Helen Spencer & Jabulani Sithole for
statistical assistance
Medical Research Council for PhD funding
Reasoning scores as a function of type
of hearing impairment
70
Non Verbal
60
50
t-score
40
30
20
10
0
No
O
Un
M
Se
M
Pr
M
ild
od
of
ve
n
ila
E
e
ou
er
t
re
er
at
nd
al
e
Reasoning scores as a function of type
of hearing impairment
64
Non Verbal
62
60
58
t-score
56
54
52
50
48
46
No
O
Un
M
Se
M
Pr
M
ild
od
of
ve
n
ila
E
e
ou
er
t
re
er
at
nd
al
e
Reasoning scores as a function of type
of hearing impairment
70 Verbal
60
Non Verbal
50
t-score
40
30
20
10
0
N
O
U
M
Se
M
Pr
on
ni
M
ild
od
of
ve
E
la
e
ou
e
re
te
ra
nd
ra
t
e
l
Reasoning scores as a function of type
of hearing impairment
70 Verbal
60 Non Verbal
50
t-score
40
30
20
10
0
N
O
U
M
Se
M
Pr
on
ni
M
ild
od
of
ve
E
la
e
ou
e
re
te
ra
nd
ra
t
e
l
Why does the prevalence
increase with age?
Is it…
new cases (i.e. acquired losses)?
progressive nature of mild cases?
late onset?
persistent OME?
Related docs
Other docs by UUU5Mu
