Keywords
hearing - language - clinical protocols - deafness
Introduction
The first years of life are considered critical for the development of the child.
It is in childhood that the apex of the maturation process of the central auditory
system occurs, as well as of the neuronal plasticity.[1] In view of this, the early detection of hearing impairment is fundamental to minimize
the losses and impacts caused by hearing loss in the development of language and of
the hearing abilities of children.[1]
[2]
[3]
In this context, assessing the hearing of a young child requires health professionals
to know the normal development of the child according to the corresponding age group.
Currently, physicians and speech-language pathologists have at their disposal objective
and subjective examinations, which, if properly applied, allow the efficient diagnosis
of hearing loss in children at an early age,[4] and when the auditory evaluation answers lead to the diagnosis of hearing loss,
regardless of the degree of impairment, it is necessary to seek auditory rehabilitation
through conventional or implantable prostheses.[5]
After adjusting the hearing device, it is essential to follow the evolution of the
case, with frequent audiological adjustments and monitoring of speech acquisition
and oral language.[3] The evaluation of these skills through standardized tests is important, since the
documentation and the systematic analysis of the evolution of the child allow adequate
orientation to the family and subsidizes the therapeutic conduct.[6]
[7]
Based on the National Health Policy for Persons with Disabilities implemented by the
Ministry of Health throughout Brazil[8] and on the advent of the compulsory newborn hearing screening,[9] the number of deaf children who access hearing health services has increased, and
the age of intervention has decreased, as recommended internationally, which is favorable
to the development of hearing and oral language skills.[3]
In the hearing health services accredited by the Brazilian Public Health System (SUS,
in the Portuguese acronym), the evaluation of hearing and language skills is essential
and is foreseen in the general guidelines for the attention of the hearing impaired.[10] Currently, the protocols used in the hearing health services in Brazil, such as
meaningful use of speech scales (MUSS), infant-toddler meaningful auditory integration
scale (IT-MAIS), Glendonald auditory screening protocol (GASP), meaningful auditory
integration scale (MAIS), functioning after pediatric cochlear implantation (FAPCI),
minimum hearing capacity evaluation test (TACAM, in the Portuguese acronym), Inventory
Development Communication (IDC), and parents' evaluation of aural/oral performance
of children (PEACH), are all international protocols translated into Portuguese.[11] In places highly sought by patients,[12] the use of many instruments could make it unfeasible to follow-up patients with
hearing aids, both implantable and non-implantable.
In the hearing health service of the Hospital Infantil (Curitiba, state of Paraná,
Brazil), the team of speech-language pathologists, after using the international instruments
to register and provide information about the hearing and oral language development
of the implanted patients, realized the need to elaborate a protocol to cover regional
demands, that is, a protocol that is simple and quick to apply and easily understood
by the parents/guardians. It was in this context that the Brazilian Scale for the
Development of Hearing and Language (EDAL-1, in the Portuguese acronym) emerged,[13] a rapid protocol composed of four tests, each one aimed at the evaluation of children
in certain age groups.
The EDAL-1,[14] the first battery test, which is the object of study in the present article, consists
of 20 questions to be answered by the parents or guardians of deaf infants/children
who have received cochlear implants at < 2 years of hearing age, and is intended to
evaluate the evolution of hearing and oral language skills after the prosthesis implantation.
The objective of the present study was to validate the EDAL-1 protocol ([Table 1]) and to establish the normality curve in normal hearing infants and children aged
between 0 and 24 months old.
Table 1
Brazilian Scale of Hearing and Language Development (EDAL-1, in the Portuguese acronym)
|
Question
|
Behavior
|
Yes
|
No
|
|
1
|
a- Do you think your child listens?
b- Was the child's adaptation to the device positive?
|
|
|
|
2
|
a- Has your child ever had ear problems? Which were they?
b- Does your child use the device more than 6 hours a day?
|
|
|
|
3
|
a- Does he/she like to listen to music or TV?
b- Does he/she handle the hearing device?
|
|
|
|
4
|
a- Does he/she like noisy toys?
b- Does his/her behavior change when he/she is wearing the device?
|
|
|
|
5
|
a- Does he/she react to loud sounds?
b- Does he/she emit more vocalic sounds when he/she is wearing the device
|
|
|
|
6
|
a- Does he/she wake up with noises?
b- Does he/she get disturbed when the device does not work?
|
|
|
|
7
|
Does he/she respond when called by name in a silent environment?
|
|
|
|
8
|
Does he/she respond when called by name in a noisy environment?
|
|
|
|
9
|
Does he/she respond to environmental sounds of everyday life? Which ones?
|
|
|
|
10
|
Does he/she vocalize during communicative interactions?
|
|
|
|
11
|
Does he/she use speech/vocalizations to attract the attention of others? Which ones?
|
|
|
|
12
|
Do vocalizations vary according to the situation?
|
|
|
|
13
|
Does he/she try to imitate sounds, words or vocalizations? Which ones?
|
|
|
|
14
|
Does he/she move his/her body when he/she hears music?
|
|
|
|
15
|
Does he/she identify different voices?
|
|
|
|
16
|
Does he/she discriminate different sounds: voice, toys, music?
|
|
|
|
17
|
Does he/she respond to simple questions without gesture support?
|
|
|
|
18
|
Does he/she speak isolated words? Which ones?
|
|
|
|
19
|
Is his/her vocabulary widening?
|
|
|
|
20
|
Does he/she speak words in sequence? Which ones?
|
|
|
Source: Ribas A, Kochen AP.[13]
Method
This is an experimental, descriptive study, approved by the Research Ethics Committee
under the number CEP/1.761.002. All of the participants signed the informed consent
form, authorizing the use of the data collected.
A total of 92 children and their relatives (parents/guardians), randomly selected
from the waiting room of the pediatric health service have participated, with 49 being
male and 43 female. The study included children whose parents denied the presence
of hearing loss. The data collection took place during the year of 2016.
The parents were approached by the speech therapist/researcher in the waiting room
of the service and invited to evaluate the hearing of their children, and then to
respond to a questionnaire. The study included infants and children aged between 0
and 24 months old at the time of the evaluation, who did not have hearing loss reported
by the parents and/or no hearing loss observed in the auditory evaluation. Infants
and children with otorhinolaryngological complaints, or with neurological and syndromic
impairments capable of interfering with the auditory development, were excluded.
Data collection took place in two steps: Step 1—otoscopy, acoustic immittance, and
behavioral observation audiometry (BOA). The audiological evaluation was performed
in an acoustic booth. Step 2—application of the EDAL-1 on the parents of the child.
The otoscopy was considered normal when there was no alteration of the meatus and
of the auditory canal capable of interfering in the auditory acuity of the child.
The tympanometric curves, obtained through the Interacoustics AD-629 audiometer (Interacoustics,
Middelfart, Denmark), were classified according to the Federal Council of Speech and
Hearing Therapy (CFFa, in the Portuguese acronym) standards.[15]
The BOA is unreliable to determine auditory thresholds, but it has been performed
to distinguish normality from alteration and to qualify the development of the auditory
function, allowing, consequently, to verify the maturation of the central auditory
nervous system.[16] For the evaluation, a set of musical instruments that must have been evaluated beforehand
in terms of frequency spectrum and intensity is required. We have used the following
musical instruments: rattle (40dB); rattle (50dB); bell (65dB); castanet (75dB); cowbell
(85dB); and snare drum (100dB). The stimuli are presented in ascending order of intensity,
for approximately three seconds, in the lateral plane to the ear in infants ≤ 9 months
old, and above the head for infants and children > 9 months old, always within 20
cm from the ear.[17] The behavioral auditory responses are qualitatively analyzed. The examiner completes
the examination by calling the child by name and asking simple questions to check
the reaction to the human voice.
The EDAL-1 is a protocol consisting of 20 closed questions, which allow a quantitative
analysis of the responses.
The instrument should be applied to the parents of the child being evaluated. Questions
1a, 2a, 3a, 4a, and 6a are intended for hearing children, and questions 1b, 2b, 3b,
4b, 5b, and 6b are intended for children with hearing aids. The answer to the question
may be positive (worth 5 points), or negative (worth zero points), except for question
2a, which was reversed because its response being positive becomes a negative point
in the evaluation. Each question with a yes answer is worth 5 points. At the end of the assessment, the number of positive responses
is added, and it can range from zero to 100. The higher the score, the better the
child is developing.
According to Damourette et al,[18] the development of hearing and language in infants and children from 0 to 24 months
old occurs in a gradual and sequential way. Each step that is overcome serves as the
basis for the next one. In this way, in terms of oral language, the child goes through
periods of simple vocalizations, shouts, babbling, imitation of vowels followed by
consonant sounds, speaking isolated words, and finally building expressions with a
vocabulary of ∼ 20 words. Regarding hearing, children pay attention to the sounds
of the world, react to their name, take an interest in the sounds around them, know
objects and people by name, and understand simple orders.
Thus, in addition to the quantitative analysis, the EDAL-1 allows a qualitative verification
of the productions of the child, both regarding his/her auditory behavior and oral
language, because the speech-language pathologist can record for each question how
and what the child under evaluation produces from the point of view of the parents/guardians.
A longitudinal analysis of the results of the EDAL-1 can be performed to verify an
increase of the score throughout the development of the child. In this way, the result
obtained with the EDAL-1 can be compared with the subsequent results of the children
in order to trace an evolutionary line of their hearing performance and oral language,
or it can be compared with the results of other children, seeking to determine deviations
from normality. Like many questionnaires answered by parents/guardians, the main limitation
is that they are indirect measurement instruments based on the responses of an observer.
In the present study, the results obtained in the EDAL-1 were treated qualitatively
and compared with auditory behavioral responses to determine their normality pattern.
Results
The 92 infants/children who composed the sample were categorized according to age,
considering age groups of three months. Boys and girls were included in all age groups.
The total was 49 boys and 43 girls. All of the infants/children had normal otoscopy
results and type A tympanometric curves.
The results are shown in [Fig. 1], where it is possible to verify that as the child grows, the more consistent are
the responses to the sound.
Fig. 1 Results observed in the behavioral observation audiometry (N = 92).
The voice responses are shown in [Fig. 2], where it is also possible to verify that the auditory response improves as the
child grows.
Fig. 2 Test result for verbal sounds (N = 92).
[Table 2] shows the results obtained with the EDAL-1. The average answers found for each period
of 3 months of age shows an increasing scale accompanying the chronological evolution
of the child. The maximum point of positive responses in the protocol is found when
the chronological age reaches 24 months.
Table 2
Results of the Brazilian Scale of Hearing and Language Development (EDAL -1, in the
Portuguese acronym) (N = 92)
|
Months
|
Number
|
Minimum
|
Maximum
|
Average
|
SD
|
Mean
|
|
0–3
|
13
|
25
|
50
|
34.23
|
8.12
|
30
|
|
3.1–6
|
16
|
40
|
70
|
54.68
|
8.65
|
55
|
|
6.1–9
|
10
|
60
|
85
|
73.0
|
10.59
|
75
|
|
9.1–12
|
10
|
65
|
100
|
82.50
|
10.34
|
80
|
|
12.1–15
|
10
|
75
|
100
|
87.0
|
7.52
|
85
|
|
15.1–18
|
10
|
85
|
100
|
91.0
|
5.16
|
90
|
|
18.1–21
|
10
|
80
|
100
|
92.50
|
6.34
|
95
|
|
21.1–24
|
13
|
85
|
100
|
95.83
|
5.06
|
95
|
Abbreviation: SD, standard deviation.
[Fig. 3] demonstrates the normality curve for the EDAL-1, considering the results obtained
in each age group. The standard deviation observed in each age group is shown in [Table 2] and complements the graph.
Fig. 3 Normality curve of the Brazilian Scale of Hearing and Language Development (EDAL-1, in the Portuguese acronym).
Discussion
The present study discusses the development of a hearing and language scale for evaluation
in a speech therapy ambulatory for the follow-up of cochlear implanted infants/children.
To do so, it took into account a behavioral-based hearing test[17] that allowed the determination of the hearing level of the infants/children assessed,
both quantitatively and qualitatively, as well as a standard language development
scale[18] recognized in the literature.
The EDAL instrument was developed to be applied to the parents or guardians of the
child, considering the age range for which it is intended. Although observation of
behavior in ludic situations gives better subsidies to the examiner, tests based on
answers by the parents are routinely used,[19] since they do not require the cooperation of the child and less time is spent, which
is consistent with the reality of the SUS ambulatories. Studies[1] show that the sooner the diagnosis of deafness is made, the better the results of
intervention and rehabilitation, so that the development of the deaf child can be
closer to the hearing peers and evaluating these responses in infants/children under
24 months old can be an arduous task, especially in cases of deafness.[19]
According to [Fig. 1], all of the infants/children who participated in the present study presented positive
answers for the auditory evaluation, confirming the information that the group studied
was of normal hearing infants/children. A study conducted with Brazilian children[17] concluded that the auditory abilities progress with the passage of time, from birth
until 12 months old, when the infant can locate the sound source in all directions.
This period is known as pre-linguistic and corresponds to the first year of life and
it is when the baby establishes the basis of communication with those around him.
It can be said that, at this stage, the child learns to listen, and the perception
of speech sounds is the first step in understanding oral language[20].
The normal development of the child still intrigues and impresses speech therapists
and other professionals who study language and hearing, for its beauty and complexity.
Although several studies[11] describe how this process occurs, in some cases the creation of instruments with
differentiated criteria becomes necessary. This is the case of hearing health services,
where the indication and adaptation of hearing aids for deaf children occurs. These
services are highly sought by patients,[12] and there is a preference for fast protocols that verify the evolution of the patient
without, however, compromising the agenda that is, in general, extensive.[19] In this sense, in response to this need, EDAL-1 was developed, which has an average
application time of 4.28 minutes, ranging from 2.30 to 11.30 minutes.[13]
Although it is an indirect measurement instrument that is based on the responses of
an observer, when the bidirectional interaction between parents and children is considered,
it is necessary to realize that communication is dependent on this interaction.[11] Therefore, based on this assumption, it was possible to establish the normality
curve of the EDAL-1 for every 3 months of age, between 0 and 2 years old, as shown
in [Fig. 3].
According to the results, it was verified that the score increases as the age increases.
Other more complex protocols,[11]
[21]
[22] which also make cross-sections, verified the same phenomenon, indicating that increasing
age promotes maturation of behavior.
Hearing is a natural human process upon which learning is built.[23] In this way, the development of oral language skills is imbued with auditory learning,
which means, insofar as the children learn to listen, they build the linguistic framework
and learn to speak.[24] This process could be verified in the present study, especially when comparing the
results of [Figs. 1] and [2]. In [Fig. 1], it is possible to visualize the increase in the number and complexity of behavioral
responses to the sound stimuli as the chronological age of the child progresses. Infants
aged between 0 and 3 months old only react reflexively and instinctively to sound.[17] More mature children learn to locate the sound source in several directions. The
same reasoning applies to [Fig. 2], where it is possible to verify that very small children react with attention to
the voice and then, as they grow, respond to simple orders.
Finally, since the EDAL-1[13]
[14] is intended for the rapid evaluation of infants and children who have received cochlear
implants between 0 and 2 years old, it is important to emphasize that the comparison
of the child evaluated with the gold standard will not always be equivalent due to
the multivariate factors that interfere with the rehabilitation of the deaf child.[25] The objective of the group of professionals of the public service where the protocol
EDAL-1 was developed was fulfilled. It has also been shown that, characterizing the
evolution of a particular child, it is possible to compare the results with a group
(here proposed as the gold standard of the test), or with his own results, considering
the previous results of the child.
Although the respondents stated that the language used in the protocol is clear, a
limitation of the present study was not having verified the internal consistency of
the protocol by a statistical index, as the literature advocated.[11] For this, it would be necessary to apply the same protocol twice, to the same respondents,
in a determined interval of time, which was not performed in the present research.
Conclusion
The normality curve for the EDAL-1 was successfully established. The averages obtained
can be considered as the standard of normality for the test, serving as a reference
for comparison with other populations.
