OCCURRENCE OF HEARING SCREENING FAULTS IN STUDENTS Ocorrência de falhas na triagem auditiva em escolares

Conflict of interest: non-existent The sensory deprivation associated with the lack of stimulation, often related to the unfavorable sociocultural environment of the child, can be a limiting factor for good academic performance, mainly for children in the early literacy process 6. The term screening refers to the process of applying fast and simple measures to a large number of individuals in order to identify a high probability of disease in individuals tested. Screening is not a diagnostic procedure, but a way to identify, among asymptomatic individuals, those who are suspected of having the disease and require more elaborate diagnostic procedures. In the case of the hearing screening in children, this aims to finalize or minimize the effects that hearing loss can have in the learning process of the individual 3,7. Among the different tests used in screening programs, the otoacoustic emissions (OAE) have an ideal profile because of its fast and non-invasive procedure along with its high reliability. Furthermore, the screening using otoacoustic emissions provides fewer false positives and false negatives results8. The Brazilian Society of Otology estimates that 10 to 15% of school-age children have mild fluctuating hearing loss and 2% have hearing loss that would require the use of sound amplification devices 9.  INTRODUCTION


INTRODUCTION
Hearing loss in infancy has a major impact on the child, which also reflects on the family and on the environment.Such alterations interfere with language and verbal skills development, and might cause learning difficulties and deleterious effects on the emotional, cognitive, academic and social development of the child 1,2 .
Hearing screening programs (HSP) with children enrolled in Early Childhood Education aim to prevent difficulties in the development of oral and written language as both are directly related to hearing [1][2][3] .Approximately 50% of hearing losses could be avoided or have their consequences reduced if early measures of identification, diagnosis and rehabilitation were conducted, especially in school-age children 4,5 .
product otoacoustic emission (DPOAEs), with the ERO SCAN analyzer from MAICO.The criterion for passing the exam was a difference of signal and noise levels above 6 dB in at least three frequencies.The data collected were recorded on a standardized protocol.
Children from four to six years of age who were attending school at the moment of data collection were included in the study.Children with agenesis of the ear canal and those whose parents refused the participation in the study were excluded from the sample.
This study was submitted for analysis by the Research Ethics Committee of the State University of Health Sciences of Alagoas -UNCISAL and obtained its approval on the protocol of number 779.
A letter to parents explaining the test results and possible causes of failure in the exam were handed to all children who participated in the HSP.The students who failed the HSP were referred for auditory diagnosis, complete ENT evaluation, and follow up in reference centers.Lectures were conducted in schools in order to orient and guide parents and teachers from these schools.
The variables gender and school system (public and private) were analyzed based on the observed results.
Statistical analysis employed the chi-square test, with a significance level of p <0.05.
The ratio of the failure frequency comparing the two school systems was calculated.

RESULTS
Ninety children enrolled in kindergarten and first grade of elementary education were evaluated.Of these children, 56 (62.3%) passed and 34 (38.7%)failed the hearing screening program.Regarding the gender of these students, 26 (46.4%) girls and 30 (53.6%) boys passed the screening and 14 (41.2%)girls and 20 (58, 8%) boys failed the hearing screening.This data revealed a significant gender difference at p <0.05 according to data presented in Table 1.
Twenty-two children failed in both ears and 11 failed in only one ear.
Of the 90 children assessed, 52 were enrolled in the public school and 38 were enrolled in the private school.From the public school, 25 (27.8%)children passed and 27 (30%) failed the screening whereas 32 (35.6%) children from private school passed and six failed (6.6%) the screening.
Statistical analysis indicated a significant difference between schools of different systems when comparing the results of the hearing screeningp <0.05 (Figure 1).
The most common type of hearing loss in schoolage children is the conductive loss, determined by middle ear infection 10,11 .The hearing losses are usually presented in mild or moderate degrees and can cause, as its consequence, phonemic changes in speech and writing.Students with this type of hearing loss are often inattentive because they have more difficulty in listening to the teacher than to the colleague on their side 12 .
Several diseases can cause hearing loss, leading to impairment in school performance, and even repetition and increased evasion rates.These diseases occur in the external, middle and inner ear, at any age range.The most common examples are impacted ear wax, foreign bodies, tube obstruction, otitis, external ear malformation, among others 13,14 .
Otitis media is among the alterations most often found in school-age children and approximately 80% of children in school age suffer from temporary hearing loss during the school year.This temporary hearing loss can cause serious problems in auditory perception and, consequently, learning difficulties, such as loss of hearing, acoustic parameters confusion, inability to perceive sounds and their meanings in speech, failure in speech abstraction and subliminal standards 14 .
Therefore the detection of hearing impairment in school-age children is of fundamental importance, especially for those who are in the literacy process.The diagnosis allows timely referral to specialized professionals, which favors the treatment and prevention of cognitive, emotional, social and communicative alterations and especially school failure.
Considering the obtained pass/fail results of the hearing screening program, this study aims to determine the frequency of failures detected in schoolage children from four to six years of age and to compare the findings of public and private schools in Maceió.

METHOD
Ninety children (52 children enrolled in a public school and 38 children enrolled in a private school in the same neighborhood of the city of Maceió) were selected for convenience and participated in the study.
The hearing screening program (HSP) in schoolage children was held in quiet rooms of the schools.The following procedure was carried out: otoscopy, using the otoscope HINNE MINE 2000 CE, in order to identify the students who have impacted ear wax or foreign body in external auditory canal (EAC).Children without EAC obstruction were submitted to the hearing screening composed by distortion  The ratio of failure frequency comparing the two educational systems indicated that students enrolled in public school fail 4.5 times more than private school children (Table 2).
Otoscopy examination was performed in 180 ears, of which 142 ears (78.8%) had open external ear canal and 38 ears (21.2%) had partial or total obstruction by wax, and of these 28 (73.60%)ears were from public school children and 10 (26.40%) ears were from private school children.
Considering the ears with open ear canals, 61 (53.0%) of children from private and 54 (47.0%) children from public schools passed the hearing screening.Five (25%) ears screened in private school and 15 (75%) ears in public school failed the OAE screening (Figure 2).Among the ears with partial obstruction identified with impacted ear wax which hearing screening was held in the public school, eight ears (72.7%) passed and three ears (27.3%) failed the screening using OAE.In the private school, four (80.0%) ears with partial obstruction passed and one ear (20.0%) failed the screening.These data are displayed in Figure 3.

School
In the private school, five (6.6%) ears with total wax obstruction were identified whereas in public school this number was 17 (16.3%),being the regarded considered as failure in the HSP.Statistical analysis indicated significant otoscopy differences between the schools with a significance of p <0.05.compared to those from the private school, corroborating with findings from the literature 14,[24][25][26][27] .This suggests that the population of public schools have less access to information on hearing health, especially with regard to the function of ear wax and the constant use of flexible rods.

CONCLUSION
The data from the current study suggests that, in the analyzed population, the occurrence of hearing screening failure in school-age children is 37.8%.Furthermore, the findings indicate that the frequency of failure is significantly higher in children from the public school when compared to children from the private school.

Figure 1 -
Figure 1 -Comparative analysis of pass/fail results according to school system (Public and Private)

Figure 2 -
Figure 2 -Comparative analysis of EAC, school system and hearing screening program with OAE

Figure 3 -
Figure 3 -Relationship between EAC, school system and hearing screening with OAE

Table 2 -Hearing Screening Program (HSP) results according to school system (Public and Private)
Note N -number of subjects Note: EAC -external acoustic canal; OAE -otoacoustic emissions