Prevalence of A1555G mitochondrial mutation in Chinese newborns and the correlation with neonatal hearing screening

Objective

To investigate the feasibility of genetic screening for deafness causative genes in the process of newborn hearing screening in China.

Methods

Total 865 newborn babies between November 2009 and March 2010 were enrolled for the simultaneous hearing and deafness causative gene screening in Tongji Hospital, Wuhan, China. Hearing screening followed a two-stage strategy with transient evoked otoacoustic emissions. Infants referred after the second-stage screening were tested by diagnostic auditory brainstem response (ABR). Genomic DNA was extracted from heel blood of newborns, and the mitochondrial 12S rRNA A1555G mutation was detected by polymerase chain reaction (PCR) based restriction fragment length polymorphism and confirmed by DNA sequencing.

Results

In hearing screening, 134 out of the 865 newborns (15.5%) were referred after the first-stage screening and 86.6% (116/134) of them returned for the second stage. After the second-stage screening, 15 who were still referred were tested by diagnostic ABR and 3 of them failed the test. On the other hand, gene screening identified 6 of the 865 newborns (0.7%) harbored homoplasmic 12S rRNA A1555G mutation although they passed the hearing screening.

Conclusion

It might be practical and effective to complement routine hearing screening in newborns with gene screening for the purpose of early diagnosis and discovery of the late-onset hearing loss.     

The economics of screening infants at risk of hearing impairment: an international analysis

Objective

Hearing impairment in children across the world constitutes a particularly serious obstacle to their optimal development and education, including language acquisition. Around 0.5-6 in every 1000 neonates and infants have congenital or early childhood onset sensorineural deafness or severe-to-profound hearing impairment, with significant consequences. Therefore, early detection is a vitally important element in providing appropriate support for deaf and hearing-impaired babies that will help them enjoy equal opportunities in society alongside all other children. This analysis estimates the costs and effectiveness of various interventions to screen infants at risk of hearing impairment.

Methods

The economic analysis used a decision tree approach to determine the cost-effectiveness of newborn hearing screening strategies. Two unique models were built to capture different strategic screening decisions. Firstly, the cost-effectiveness of universal newborn hearing screening (UNHS) was compared to selective screening of newborns with risk factors. Secondly, the cost-effectiveness of providing a one-stage screening process vs. a two-stage screening process was investigated.

Results

Two countries, the United Kingdom and India, were used as case studies to illustrate the likely cost outcomes associated with the various strategies to diagnose hearing loss in infants. In the UK, the universal strategy incurs a further cost of approximately £2.3 million but detected an extra 63 cases. An incremental cost per case detected of £36,181 was estimated. The estimated economic burden was substantially higher in India when adopting a universal strategy due to the higher baseline prevalence of hearing loss. The one-stage screening strategy accumulated an additional 13,480 and 13,432 extra cases of false-positives, in the UK and India respectively when compared to a two-stage screening strategy. This represented increased costs by approximately £1.3 million and INR 34.6 million.

Conclusions

The cost-effectiveness of a screening intervention was largely dependent upon two key factors. As would be expected, the cost (per patient) of the intervention drives the model substantially, with higher costs leading to higher cost-effectiveness ratios. Likewise, the baseline prevalence (risk) of hearing impairment also affected the results. In scenarios where the baseline risk was low, the intervention was less likely to be cost-effective compared to when the baseline risk was high.     

Universal newborn hearing screening in the Champagne-Ardenne region: A 4-year follow-up after early diagnosis of hearing impairment

Introduction

Permanent congenital hearing loss is one of the most frequent congenital anomaly at birth. Universal newborn hearing screening (UNHS) was introduced in numerous countries in order to allow an early diagnosis and intervention for congenital hearing impairment.

Objective

First aim of this study is to evaluate the accuracy of early diagnosis of hearing impairment after UNHS. Second aim is to discuss the auditory intervention proposed after this diagnosis. Last aim is to evaluate the relevance of UNHS for early diagnosis and intervention.

Materials and methods

Prospective study. UNHS program was introduced in the entire French region of Champagne-Ardenne in January 2004. Forty-one children have benefited of an early diagnosis of hearing impairment until June 2007. They were included in an intervention program consisting of an audiometric follow-up and an auditory intervention. This program was conducted until June 2008.

Results

There were 28 males patients and 13 females patients. The diagnosis of hearing aid impairment was carried at an average age of 3.2-month. The auditory follow-up allowed confirming the initial diagnosis of deafness for the majority of the children as for their degree of hearing loss. Auditory intervention was heterogeneous depending on degree of hearing loss of the children.

Conclusion

This UNHS program demonstrates its validity and feasibility for early diagnosis and intervention of congenital hearing impairment. It brought a major impact on the management of congenital hearing impairment in Champagne-Ardenne.     

Prognostic validity of dichotic multiple frequencies auditory steady-state responses versus distortion product otoacoustic emissions in hearing screening of high risk neonates

Objective

To determine the validity of dichotic multiple frequencies auditory steady-state responses (ASSR) as a hearing screening technique versus using distortion product otoacoustic emissions (DPOAEs) among high-risk neonates.

Methods

A cross sectional study was performed on 118 high-risk neonates by means of dichotic multiple frequencies ASSR and DPOAE for hearing screening. DPOAE results were used as the standard for hearing screening in parallel with ASSR. Dichotic multiple frequencies ASSR results were analyzed by means of F-value of less or greater than 0.05 criteria as a pass-fail for the responses. Dichotic multiple ASSR hearing screening technique was considered in two intensity levels at 40 and 70 dB HL. The ASSRs thresholds were measured in high risk neonates with and without hearing deficits as determined by DPOAES. The results of ASSR and DPOAE were compared to be gathered by contingency table in order to obtain sensitivity, specificity and other different statistical values. Average performing times for the tests were analyzed.

Results

The specificity of dichotic multiple ASSR was 92.6%, 93.8% and the sensitivity was 71.6%, 62.2% at the 70 and 40 dB hearing levels, respectively. Mean ASSR thresholds for normal-hearing infants at an average corrected age of 6 days were 32.2 ± 12.2, 29.8 ± 10.2, 26.2 ± 11.4 and 30.4 ± 10.8 dB HL for 0.5, 1, 2 and 4 kHz, respectively. The average times for performing the tests were 18.7 and 32.9 min respectively.

Conclusions

ASSR with this special paradigm is a fairly desirable method for hearing screening of high-risk neonates. There is good concordance between ASSRs and DOPAEs results among high risk neonates referred for hearing screening. The sensitivity and specificity of this test is sufficient for hearing screening in high risk neonates. This test could be valuable for rapid confirmation of normal thresholds. As long as further research have not been conducted on ASSR, great caution should be made to interpret the results of ASSR as a hearing screening technique in young infants and also additional techniques such as the tone-evoked ABRs should be used to cross-check results. It's still too soon to recommend ASSRs as a standalone electrophysiologic measure of hearing thresholds in infants.     

Maternal smoking during pregnancy: impact on otoacoustic emissions in neonates

Objectives

To determine the effect of maternal smoking during pregnancy on transient evoked otoacoustic emissions levels in neonates.

Methods

This was a cross-sectional study investigating neonates in the maternity ward of a university hospital in the city of São Paulo, Brazil.A total of 418 term neonates without prenatal or perinatal complications were evaluated. The neonates were divided into two groups: a study group, which comprised 98 neonates born to mothers who had smoked during pregnancy; and a control group, which comprised 320 neonates born to mothers who had not.In order to compare the two ears and the two groups in terms of the mean overall response and the mean transient evoked otoacoustic emissions in response to acoustic stimuli delivered at different frequencies, we used analysis of variance with repeated measures.

Results

The mean overall response and the mean frequency-specific response levels were lower in the neonates in the study group (p < 0.001). The mean difference between the groups was 2.47 dB sound pressure level (95% confidence interval: 1.47-3.48).

Conclusions

Maternal smoking during pregnancy had a negative effect on cochlear function, as determined by otoacoustic emissions testing. Therefore, pregnant women should be warned of this additional hazard of smoking. It is important that smoking control be viewed as a public health priority and that strategies for treating tobacco dependence be devised.     

Appropriate hearing screening in the pediatric patient with head trauma

Purpose

To develop an algorithm for the appropriate audiologic screening of in children with head trauma.

Methods

Participants were the first consecutive 50 children admitted to a children's hospital trauma service after October 1, 2005, whose injuries resulted in a Glasgow Coma Scale (GCS) score ≤13 and/or loss of consciousness (LOC) but no history of hearing loss. Screening tympanometry, otoacoustic emissions testing, and/or routine audiometric evaluation were performed as soon as possible after admission. Age, GCS score, Pediatric Trauma Score, Injury Severity Score, presence of head and neck soft tissue injury, temporal bone fracture, skull fracture not involving the temporal bone, midface/mandible fractures, intracranial abnormality on computed tomography, and cervical fracture were analyzed as risk factors for hearing loss.

Results

Seventeen (34%) of the 50 children had abnormal hearing test results. Fischer's exact test showed abnormal test results were most strongly related to temporal bone fracture (p = 0.0041), non-temporal bone skull fracture (p = 0.0211) and younger age (p = 0.0638).

Conclusions

Any child with head trauma and clinical or radiologic evidence of temporal bone fracture should have early hearing evaluation. Using the proposed algorithm to test children with head trauma and GCS ≤13 and/or LOC and age <3 years or any type of skull fracture may help identify children with hearing loss in a more cost effective manner.     

Qualitative analysis of parents’ experience with receiving the news of the detection of their child's hearing loss

Objective

Despite the fact that clinicians are responsible for delivering bad news, they have been shown to lack both confidence and skill in performing this basic task. The time immediately after the detection of childhood hearing loss is perceived as stressful. We conducted a qualitative study to assess parents’ experiences with receiving the bad news of the detection of their child's hearing loss.

Study design

Semi-structured interviews were conducted with families of children with hearing loss identified during early childhood.

Setting

A rehabilitation center treating pre-school children in the north of Israel.

Patients

14 families/parents of children diagnosed prior to the implementation of a universal screening program.

Main outcome measure

Parents’ perceptions of the manner in which the information regarding the detection of their child's hearing loss was given, and what their feelings were at the time.

Results

50% of parents expressed dissatisfaction with the process of the breaking of the bad news. ABR is perceived by parents and health professionals alike as the definitive moment of diagnosis. The emotions experienced by parents at the moment of the breaking of the bad news were predominantly shock and upset. The meaning of the news was perceived differently under different circumstances. Information given bluntly, without empathy, was a frequent complaint. Parents repeatedly stated the importance of the formulation of a plan for the future.

Conclusions

Qualitative enquiry provided valuable information. Effective strategies for the breaking of bad news should become an integral part of universal neonatal screening programs.     

A normative study of otoacoustic emissions, ear asymmetry, and gender effect in healthy schoolchildren in Slovakia

Objective

The aim of this normative study was to examine cochlear status and possible ear asymmetry and gender effect in transient evoked and distortion product otoacoustic emissions in a group of healthy 12-year-old children in Slovakia.

Methods

Two hundred and twenty-nine 12-year-old children from Slovakia with normal hearing were included in this study. Adolescents with acute infection, abnormal otoscopic findings and abnormal tympanometry were excluded. Pure tone audiometry was performed in standard conditions in a sound proof room. Recordings of transient evoked (TE) and distortion product otoacoustic emissions (DPOAEs) were performed using an ILO 292 USB Echoport. Parameters of hearing thresholds and OAEs were compared using correlation analysis and Wilcoxon test.

Results

We found highly statistically significant associations between the hearing thresholds for the left and right ears. When comparing pure tone audiometry with OAEs no significant correlation was found. In TEOAE a significant gender effect and side effect in TEOAE SNR were found. On the other hand there was no side effect in TEOAE response level. In DPOAE neither gender nor side effects were determined.

Conclusions

This is the first comprehensive information on cochlear status among Slovak adolescents. The TEOAEs were significantly higher in girls than boys, but the ear asymmetry in TEOAE was not significant. For DPOAE responses ear asymmetry and gender did not play a role. The data obtained are a basis for population hearing screening, especially for hearing screening programs in infants and children in Slovakia. Moreover data from particular age group represent a link between data from infants and adults.     

Etiological diagnosis in the hearing impaired newborn: proposal of a flow chart

Objective

Most industrialized countries have introduced some form of universal newborn hearing screening program. Both identification and rehabilitation of hearing loss in newborns have evolved to an acceptable standard and the need for a standardized etiological protocol is emerging.

Methods

Extensive literature search to determine which investigations can help identifying the cause of congenital hearing loss and how to limit extensive testing in these children by taking into account the most prevalent causes.

Findings

A stepwise approach to detect the cause of hearing loss in children with congenital sensorineural hearing loss was developed.

Conclusion

In general it is advised to first rule out Cx26/Cx30 and infectious causes (cytomegalovirus and, if indicated, toxoplasmosis and rubella), and to preserve more extensive investigations for those children in whom these causes do not explain the hearing loss.     

The assessment of hearing impairment among healthy children in rural and urban areas in China

Objective

To investigate the auditory function of healthy children and provide experimental data to protect children's hearing in China.

Methods

Total of 191 normally growing children (6-12 years old) in Qinling mountain area, the pasturing area around Qinghai Lake and Nanjing city were randomly included in this study. The whole-frequency auditory thresholds of these children were examined.

Results

There was significant difference between the boys’ and girls’ auditory thresholds at nearly the whole frequencies in the Qinling area. Significant difference was also found between the boys’ and girls’ auditory thresholds at high frequencies and super high frequencies in the pasturing area around Qinghai Lake. Overall, the girls’ auditory function was much better than the boys’. In contrast, there was no significant difference between the boys’ and girls’ auditory thresholds in Nanjing city. The auditory thresholds in high frequencies and super high frequencies of the boys in Nanjing city were lower than those of the boys in mountain and plateau pasturing areas, while there was no significant difference of the girls’ auditory thresholds between city and rural areas except for a few low frequencies.

Conclusions

Hearing impairment was found in Chinese children of rural areas, especially among the boys. Since the children in rural areas should have no chance to be exposed to the modern industrial noises, it is most likely that the impulse noises from firecrackers caused the partial loss of hearings.     

Risk factors associated with hearing loss in infants: an analysis of 5282 referred neonates

Objective

The aim of our study was to evaluate the frequency of risk factors and their influence on - the distribution and manifestation of - hearing loss in infants. The study was conducted at the Department of Laryngology in the Upper Silesian Center for Child Health in Katowice (Poland), as part of the Polish National Universal Neonatal Hearing Screening, conducted from 2003 to 2009.

Materials and methods

The selected population included every newborn that twice tested positive on the transient evoked otoacoustic emission (TEOAE) screening test, as well as all neonates with one or more risk factors as defined by the Joint Committee of Infant Hearing in 2000 (JCIH).The following procedures were used with each neonate: otolaryngological examination (with otoscopy), tympanometry, automated otoacoustic emission (AOAE), and auditory brainstem response (ABR).A total of 5282 infants were examined. Subjects were categorized into two groups: the first group consisted of 2986 (56.53%) neonates with risk factors of hearing loss, while the second group included 2296 (43.47%) neonates without any known risk factors, but who twice tested positive on the TEOAE screening.

Results

Among all infants examined (5282), sensorineural hearing loss (SNHL) was identified in 240 cases (4.54%), and conductive hearing loss (CHL) in 40 cases (0.76%), while normal hearing (NH) appeared in 5002 cases (94.70%).In the first group, SNHL was identified in 128 neonates (4.29%), and CHL in 28 (0.94%), while NH appeared in 2830 (94.78%). The largest percentage of SNHL (15.52%) appeared in children with identified or suspected syndromes associated with hearing loss. The next highest frequency of SNHL was comprised of children subjected to mechanical ventilation for a period in excess of 5 days (11.45%).Only a small percentage (2.86%) of SNHL appeared to be due to the use of ototoxic medications, despite the fact that this factor is the most prevalent (33.13%) of all analyzed risk factors of hearing impairment. After ototoxic medications, the frequencies of risk factors are as follows: premature birth (16.21%); low birth weight (12.04%); intensive care in excess of 7 days (10.64%). Furthermore, as the number of coexisting risk factors increases, the probability of SNHL in infants is seen to also increase. For children with one to four coexisting risk factors, the probability of SNHL ranges from 3.15% to 5.56%; for five or more risk factors the probability nearly doubles.

Conclusion

Our results indicate that syndromes associated with hearing loss and mechanical ventilation for more than 5 days were statistically significant risk factors in the occurrence of hearing loss. The most common risk factors are ototoxic medications, premature birth, low birth weight, and intensive care in excess of 7 days. As the number of risk factors an infant is exposed to grows, the probability of hearing impairment increases. The large percentage of children with sensorineural hearing loss in the absence of any known risk factors demonstrates the necessity of hearing examinations in all neonates.     

Newborn hearing screening and genetic testing in 8974 Brazilian neonates

Objective

An early diagnosis has been a priority in the audiological practice. Identifying hearing loss until 3 months old through Universal Newborn Hearing Screening and intervention before 6 months old, minimize the impact of auditory loss in the health and communication development of these children. However, in the clinical practice, despite the help of the risk indicators in the audiological and etiological diagnosis, the integrated services have come up against the challenge of determining the causes of auditory loss, bearing in mind that approximately 50% of the subjects who have congenital loss do not show risk factors in their clinical history. The current research aims introduce together etiologic and audiological diagnosis of newborns.

Methods

We eluted dried blood spots from paper and performed genetic testing for 35delG mutation in 8974 newborns that were also screened for transient otoacoustic emissions (TOAE). In addition, the A1555G and A827G mutations in the MTRNR1 mitochondrial gene were screened in all newborns.

Results

We have found 17 individuals who failed in TOAE. Among them, we detected 4 homozygous newborns for 35delG mutation and 3 individuals with A827G mutation in the MTRNR1 mitochondrial gene. The frequency of 35delG carriers was 0.94% [84/8974]. In all 17 individuals who failed in OAE no other mutation besides those mentioned above was found.

Conclusions

The results greatly contribute to the public health area indicating the etiologic diagnosis, allowing family counseling as well as the early rehabilitation treatment or surgical intervention. Over time that will help to reduce the costs of rehabilitation considerably.     

Progressive hearing loss after completion of cisplatin chemotherapy is common and more pronounced in children without spontaneous otoacoustic emissions before chemotherapy

Objective

High frequency hearing loss following cisplatin chemotherapy is frequent in children and often necessitates the fitting of hearing aids. During therapy, hearing is usually monitored. Post-therapeutic follow-up does not routinely include monitoring of hearing, although there are indications that hearing thresholds can decline after therapy.

Methods

Pure-tone audiograms taken from 27 children (17 males, 10 females) treated with cisplatin at Muenster university hospital (mean age 9.84 years, standard deviation 3.67 years) including an audiological follow-up at least 6 months after therapy, were analyzed retrospectively.

Results

In follow-up tests after completion of therapy, 24.1% of all ears showed an increase in mean high frequency hearing thresholds (4-8 kHz). Post-therapeutic hearing deterioration was significant at 4 kHz and significantly more pronounced in children without measurable spontaneous otoacoustic emissions (SOAE) before therapy. Post-therapeutic hearing deterioration did not occur in ears with normal pure tone thresholds (≤10 dB at all frequencies) after cisplatin therapy. No correlation was found between post-therapeutic hearing deterioration and cranial irradiation.

Conclusions

Cisplatin chemotherapy follow-up should include audiological monitoring in all children with elevated pure tone thresholds after therapy. Routine SOAE measurements taken as part of baseline audiometry before the start of chemotherapy can be taken into consideration.     

Impact on hearing of routine ear suctioning at the tympanic membrane

Objective

Patient and equipment safety has become increasingly scrutinized in today's medical care. Routine otolaryngologic evaluation often involves suctioning with Frazier-type suction devices in the ear canal for improved visualization, but data are limited on the potential acoustic trauma from ear canal suction devices. This study intends to document the objective and subjective effects of ear canal suctioning to identify any risk for hearing threshold shifts or other potential negative effects.

Patients and Methods

Prospective study on 21 healthy volunteers enlisted for evaluation. Presuctioning tympanogram, audiogram, and otoacoustic emissions data were obtained. Spectrum analyses were recorded during ear canal suctioning with a probe microphone placed lateral to the tympanic membrane. Subjective data were recorded, and a follow-up audiogram and otoacoustic emissions were obtained to identify any temporary threshold shifts.

Results

Spectrum analyses revealed a high degree of variability between subjects. A peak intensity of 111 dB sound pressure level was recorded. All patients tolerated suctioning, and none reported hearing loss. No threshold shifts were observed. Subjective data failed to correlate with the objective recorded intensities.

Conclusions

Clinicians and patients need to be acutely aware of potential risks and benefits from any medical intervention. Routine ear canal suctioning can be extremely loud and uncomfortable for patients. This study failed to document objective proof of hearing detriment from ear canal suctioning, although the possibility exists during office and surgical intervention. Further study and potential alternative suctioning methods deserve attention.     

Findings from multidisciplinary evaluation of children with permanent hearing loss

Objectives

To describe clinical findings from a multidisciplinary program for children with permanent hearing loss (PHL).

Methods

Retrospective chart review at a tertiary care children's hospital. Patients: Two hundred patients charts were selected from the population of 260 children with permanent hearing loss presenting between July 2005 and December 2006. Main outcome measures: PHL etiology; radiographic findings; clinical findings by genetics, ophthalmology, developmental pediatrics, speech pathology, and aural rehabilitation.

Results

Etiology of hearing loss was determined in 60% of subjects. Genetic causes of hearing loss were identified or presumed (positive history of first degree relative with hearing loss) in 27% of the children. Structural ear anomalies were found in 20% of children. Among the 36% of children with CNS imaging, abnormal findings were noted in 32%. There were a high rate of ophthalmological findings (53%) among children seen by ophthalmology (n = 105). Neurodevelopmental evaluations were completed in 58% of subjects and clinically significant findings were noted in 68%. Of the 61% of children who receiving received speech/language evaluations, 77% required intervention. Over half of the 40% of subjects who had an aural rehabilitation evaluation needed therapy. There were not significant differences in rates of findings for children with mild or unilateral hearing loss as compared to children with more severe degrees of hearing loss.

Conclusions

Interdisciplinary medical evaluation of children with PHL allows for the identification and treatment of clinically significant ophthalmologic, neurodevelopmental, genetic, and speech/language disorders. A high rate of CNS and temporal bone abnormalities were identified. These findings provide an understanding of the importance of considering thorough medical and developmental evaluations among children who are deaf/hard of hearing.     

An initial overestimation of sensorineural hearing loss in NICU infants after failure on neonatal hearing screening

Objective

Infants admitted to neonatal intensive care units have a higher incidence of significant congenital hearing loss. We classified audiologic diagnoses and follow-up in infants who had been admitted to our neonatal intensive care unit.

Methods

We included all infants admitted to the neonatal intensive care unit at Sophia Children's Hospital between 2004 and 2009 who had been referred for auditory brainstem response measurement after failing neonatal hearing screening with automated auditory brainstem response. We retrospectively analyzed the results of auditory brainstem response measurement.

Results

Between 2004 and 2009 3316 infants admitted to our neonatal intensive care unit had neonatal hearing screening. 103 infants failed neonatal hearing screening: 46 girls and 57 boys. After first auditory brainstem response measurement we found 18% had normal hearing or a minimal hearing loss. The remainder had a type of hearing loss, distributed as follows: 15% conductive, 32% symmetric sensorineural, 14% asymmetric sensorineural, and 21% absent auditory brainstem responses. Repeated auditory brainstem response measurement showed a shift in hearing outcome. The main difference was an improvement from symmetric sensorineural hearing loss to normal hearing. However, in a small percentage of children, the hearing deteriorated.

Conclusions

As many as 58% of infants in this high-risk population who failed the neonatal hearing screening were diagnosed with sensorineural hearing loss or absent auditory brainstem responses. An initial overestimation of sensorineural hearing loss of about 10% was seen at first auditory brainstem response measurement. This may be partially explained by a conductive component that has resolved. Finally, in a small percentage of children the hearing deteriorated.     

Screening for pre-school and school-age hearing problems: European Consensus Statement

Objectives

To formulate consensus statement and policies on structured hearing screening programs in pre-school and school-age children in Europe. This consensus will be brought before the European Union's Member States as a working and effective program with recommendations for adoption.

Methods

A distinguished panel of experts discussed hearing screening of pre-school and school-age children during the 10th Congress of European Federation of Audiology Societies (EFAS), held in Warsaw, Poland, on June 22, 2011. The panel included experts in audiology, otolaryngology, communication disorders, speech language pathology, education and biomedical engineering.

Results

Consensus was reached on thirteen points. Key elements of the consensus, as described herein, are: (1) defining the role of pre-school and school screening programs in the identification and treatment of hearing problems; (2) identifying the target population; (3) recognizing the need for a quality control system in screening programs.

Conclusions

The European Consensus Statement on Hearing Screening of Pre-school and School-age Children will encourage the appropriate authorities of the various countries involved to initiate hearing screening programs of pre-school and school-age children.