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Universal Newborn Hearing Screening and Postnatal Hearing Loss


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Universal Newborn Hearing Screening and Postnatal

Hearing Loss

Viktor Weichbold, MD, MPhil, Doris Nekahm-Heis, MD, Kunigunde Welzl-Mueller, PhD

Clinical Department of Hearing, Voice and Speech Disorders, Innsbruck Medical University, Innsbruck, Austria

The authors have indicated they have no financial relationships relevant to this article to disclose.


OBJECTIVE.The goal of this study was to determine the percentage of children who

have a postnatal permanent childhood hearing impairment (PCHI) and the per-centage thereof who have risk indicators for a postnatal hearing loss.

METHODS.Data were drawn retrospectively from the clinical charts of children who

had bilateral PCHI (⬎40 dB hearing level, better ear, unaided) and had undergone universal newborn hearing screening (UNHS) between 1995 and 2000 in various Austrian hospitals. A hearing loss was recognized as postnatal when a child passed UNHS but was later found to have a hearing impairment. The presence of risk indicators, as suggested by the Year 2000 Statement of the American Joint Com-mittee on Infant Hearing (JCIH), was assessed by reviewing the children’s clinical charts.

RESULTS.Of a total of 105 children with bilateral PCHI, 23 (22%) showed postnatal

impairment. After correction of this number for underascertainment, postnatal impairment was estimated to account for 25% of all bilateral PCHI at age 9 years. Risk indicators were found in 17 children but did not fully correspond to those proposed by the JCIH. The risk factors found were a family history of hearing loss (3 children), meningitis (2), craniofacial malformation (2), persistent pulmonary hypertension (1), congenital cytomegaly infection (1), extracorporeal membrane oxygenation (1), recurrent otitis media with effusion (1), and, in addition to the JCIH list, ototoxic therapy (5), and birth before 33rd gestational week (2) (1 child had a combination of the last 2). Six children showed no risk indicators for the postnatal hearing loss.

CONCLUSIONS.Our findings suggest that⬃25% of bilateral childhood hearing loss is

postnatal, which supports the leading role of UNHS in detecting PCHI. Provisions for also identifying postnatal cases nevertheless are justified. Because in some of these children no risk indicators are detectable and in others the hearing deteri-oration starts after age 3 years, audiologic monitoring of at-risk children up to this age may not be sufficient. Additional methods, such as hearing screening at nursery schools or schools, are recommended.

www.pediatrics.org/cgi/doi/10.1542/ peds.2005-1455


Key Words

early hearing detection and intervention, permanent childhood hearing impairment, postnatal hearing impairment, risk indicators, universal newborn hearing screening


PCHI—permanent childhood hearing impairment

UNHS— universal newborn hearing screening

HL— hearing level

TEOAE—transient evoked otoacoustic emissions

ENT— ears—nose—and throat JCIH—Joint Committee on Infant Hearing

Accepted for publication Sep 29, 2005 Address correspondence to Viktor Weichbold, MD, MPhil, Clinical Department of Hearing, Voice and Speech Disorders, Anichstrasse 35, A-6020 Innsbruck, Austria. E-mail: viktor. weichbold@uklibk.ac.at



ARLY INTERVENTION FORpermanent childhood hear-ing impairment (PCHI) has been shown to reduce the deleterious effects of impaired audition on language and cognitive and social skills of affected children.1–4For

identification of hearing impairment in newborns, uni-versal neonatal hearing screening (UNHS) has been im-plemented in many parts of the Western world, but not all PCHI is detectable in infancy. Three major categories of hearing loss become manifest postnatally: delayed onset, progressive, and acquired.* Delayed-onset hear-ing loss derives from certain adverse medical conditions that are present before or around birth (eg, intrauterine infections, severe asphyxia) and whose damaging impact to the inner ear evolves over time. Thus, the child’s hearing still is normal in the perinatal period but starts to deteriorate some time afterward. Progressive hearing loss is either hereditary or linked to syndromes and neurodegenerative disorders. Presenting with normal audiologic responses at birth, these children later show a great variety regarding onset, progression rate, frequen-cies involved, and ultimate severity of their hearing im-pairment. Finally, acquired hearing loss results from a number of external factors that directly or indirectly harm the inner ear, such as meningitis, ototoxic drugs, and acoustic trauma.

For prompt detection also of postnatal PCHI, the con-tinued surveillance of infants and toddlers who are at risk for a postnatal hearing loss has been recommended, and a list of risk indicators have been proposed.5 This

recommendation raises the following questions: How many children remain to be detected in the postnatal years? Is surveillance of at-risk children sufficient to detect at least the majority of them? Evidence on the prevalence of postnatal PCHI is conflicting (Table 1). A study from the United Kingdom found the prevalence of all hearing loss ⬎40 dB hearing level (HL) to increase from 1.06/1000 at birth to up to 1.65/1000 (or even 2.05/1000; adjusted value) at age 9 years.6This would

mean that⬃35% to 50% of all hearing loss in 9-year-old children is postnatal. A study from the United States estimated the prevalence of congenital PCHI⬎40 dB HL

at 0.53/1000 and the prevalence of post(neo)natal PCHI

⬎40 dB HL at ⬃0.25/1000.7If the figures are correct,

then⬃30% of all PCHI would be postnatal. In contrast, 2 epidemiologic studies in English and Scottish birth cohorts reported that postnatal cases accounted for only 16% and 11%, respectively, of all PCHI ⬎40 dB HL.8,9

The 4 studies differ a bit in their observation periods, which, however, hardly explains the discrepancy be-tween their estimates. Instead, differences in their ascer-tainment methods and, more relevant, uncertain criteria for determining whether a hearing loss is congenital or postnatal are the likely reasons for the divergences. A postnatal hearing loss is commonly defined by onset after the perinatal period. The time of onset, however, frequently is unknown, and its determination relies on assumption. To circumvent this problem, we applied a different definition in our study: a hearing loss is post-natal when the child passed UNHS but was later found to have a hearing impairment. Clearly, this definition is not free of problems (it assumes a 100% sensitivity of the screen, and it cannot be applied to unscreened children), but it allows a clear-cut decision to be made for every screened child concerning the category into which the hearing loss falls.

With this refined definition, we analyzed data retro-spectively to determine the number of postnatal cases among children with hearing impairment. In addition, we investigated how many of them exhibited risk indi-cators for a postnatal hearing loss. This analysis was part of a larger study to evaluate the efficacy of the Austrian UNHS program. In Austria, newborn hearing screening officially started in 1995, when the national ears, nose, and throat (ENT) society issued a consensus paper on early detection of PCHI through UNHS and set up the guidelines for its nationwide implementation. According to these guidelines, UNHS is performed as a hospital-based, 2-stage screening to measure transient evoked otoacoustic emissions (TEOAE). The newborns first are tested a few days after birth and, if they fail, undergo a second test before discharge from the hospital. If they fail again (ie, fail the screening), then they are referred for audiologic assessment. Although in the early years only a few hospitals participated in the program, today it is widely implemented, such that it currently (Autumn 2005) covers⬃90% of all Austrian neonates. The yield

* These terms, including “late-onset hearing loss,” are not well defined. They seem to represent a classification scheme; however, they are based on different classification criteria, namely onset, course, and cause of hearing loss. Hence, they allow for overlap: although delayed-onset hearing loss is typically progressive, progressive hearing loss may appear at the same time as delayed-onset hearing loss.

TABLE 1 Studies That Included Information on the Prevalence of Postnatal Hearing Loss

Reference Age of Children Types of Hearing Loss Targeted Proportion of Postnatal Hearing Loss

Fortnum and Davis8(1997) 18 mo to 10 y All types 16% of the sample

van Narden et al7(1999) 3 to 10 y Congenital hearing loss: sensorineural only;

postnatal hearing loss: all types

⬃30% in children aged 3 to 10 y

Fortnum et al6(2001) 3 to 18 y All types 30–50% in children aged 9 y

MacAndie et al9(2003) 6 to 15 y All types 11% of the sample

Present study 4 to 9 y All types 22% of the sample; estimated 25% in children aged 9 y


from the screening since its inception in 1995 is judged to provide a good basis for analyzing the number of children with a postnatal PCHI.


Study Design

The study was conducted as a survey to collect retro-spective data on children who were born in Austria and received a diagnosis of a PCHI at an Austrian ENT De-partment. Of a total of 35 institutions that are engaged in the diagnosis and habilitation of childhood hearing im-pairment, 15 participated. Using a standardized form, they submitted anonymized data on all children who had PCHI and were registered with them since 1990. The form asked for the child’s date of birth, date of diagnosis of hearing loss, degree and type of hearing loss (at iden-tification), and whether the child had undergone new-born hearing screening. When yes, the result of the screen (pass/fail/unknown) was to be specified. When the reason for referral to hearing assessment was other than a failed screen, it was to be indicated (eg, menin-gitis, parental concern). Data collection started in August 2003, after the study had received approval by the Ex-ecutive Board of the Austrian ENT Society, and ran until the end of December 2004.

Study Population and Inclusion Criteria

Although the study population comprised all children who had PCHI and were born in Austria since 1990, for the purpose of this particular analysis, only data from children who met the following criteria were used: (1) bilateral sensorineural, conductive, or combined hearing impairment; (2) at least a moderate degree of hearing loss (⬎40 dB better ear HL, unaided); (3) born between 1995 and 2000; and (4) having undergone UNHS.

The end of the time frame (December 2000) was chosen to warrant at least a 4-year period after birth (data analysis started in Spring 2005), in which a post-natal hearing impairment can become manifest and be confirmed. The criteria of a bilateral and an at least moderate hearing loss were set in accordance with the literature6–9 for reasons of comparability. Hearing

im-pairment was measured in older children by pure tone audiometry and averaged over frequencies 0.5, 1, 2, and 4 kHz. In young children, results from the automated auditory brainstem response measurement were used to estimate the degree of the hearing impairment. Degrees of hearing impairment were as follows: moderate, 41 to 70 dB HL; severe, 71 to 95 dB HL; profound,⬎95 dB HL. In children who met the definition of “postnatal hearing loss,” the clinical charts were reviewed for occurrences that were considered to indicate an increased risk for postnatal onset of hearing impairment (see below). For this purpose, competent personnel at the submitting institutions were contacted and asked for assistance.

Ascertainment of Hearing Impairment

As mentioned above, all neonates were screened at var-ious Austrian hospitals (maternity wards or ICUs) using TEOAE. To pass the screen, the child had to have posi-tive TEOAE in at least 1 ear at either the first test or the retest. In this way, a bilateral congenital hearing impair-ment was excluded. Hearing assessimpair-ment of the children who failed the screen as well as of those whose hearing impairment became manifest after the neonatal period occurred at audiologic units of various Austrian ENT departments. At these institutions, TEOAE and auditory brainstem responses (in older children: pure tone audio-grams) were assessed to confirm the hearing loss.

Outcome Variables

Before data analysis, the data were checked for dupli-cates (recognized by the identicalness of dates, eg, date of birth and of hearing loss diagnosis) and for inconsis-tencies. When such were found, the submitting institu-tions were asked for clarification.

The main outcome variables were (1) the percentage of children who had hearing impairment with a postna-tal onset of hearing loss and (2) the percentage thereof with at least 1 risk indicator for a postnatal hearing loss. Risk indicators were drawn from the Year 2000 State-ment of the Joint Committee on Infant Hearing (JCIH)5:

1. Parental or caregiver concern regarding hearing, speech, language, and/or developmental delay

2. Family history of PCHI

3. Stigmata or other findings associated with a syn-drome that is known to include a sensorineural or conductive hearing loss or eustachian tube dysfunc-tion

4. Postnatal infections associated with sensorineural hearing loss, including bacterial meningitis

5. In utero infections, such as cytomegalovirus, herpes, rubella, syphilis, and toxoplasmosis

6. Neonatal indicators, specifically hyperbilirubinemia at a serum level that requires exchange transfusion, persistent pulmonary hypertension of the newborn associated with mechanical ventilation, and condi-tions that required the use of extracorporeal mem-brane oxygenation

7. Syndromes that are associated with progressive hearing loss, such as neurofibromatosis, osteopetro-sis, and Usher’s syndrome

8. Neurodegenerative disorders, such as Hunter syn-drome, or sensory motor neuropathies, such as Frie-dreich’s ataxia and Charcot-Marie-Tooth syndrome

9. Head trauma

10. Recurrent or persistent otitis media with effusion.


searched for these indicators, 2 problems arose. First, “parental or caregiver’s concern regarding hearing etc.” is a very unspecific factor that was practically always present (otherwise, the child would not have undergone hearing assessment). For this reason we decided to dis-regard it. Instead, we put the focus on the question, “Who was the person whose concern prompted the hearing assessment?” Second, some children exhibited occurrences that are not included in the JCIH list, al-though they are traditionally regarded as risk factors for hearing loss (eg, ototoxic medication). Because these occurrences could have been etiologically linked to the hearing loss in some cases, we registered them, too. To indicate that they do not belong to the JCIH risk indica-tor list, we put them in brackets in our results table (Table 2).


From a total of⬃550 notifications delivered by the par-ticipating institutions, a subset of 105 children with hearing impairment met the above criteria for inclusion in this analysis (overall results from the whole sample are reported elsewhere10,11). The hearing loss in these

105 children was bilateral sensorineural in 97, bilateral conductive in 3, and bilateral combined in 2. In 3 addi-tional children, it was sensorineural in 1 ear and com-bined in the other.

Of the 105 children, 23 had passed newborn hearing screening, indicating that 22% of the hearing loss in this sample was postnatal (95% confidence interval: 14 –

30%). Table 2 lists some details of these children. Six of them were female, and 17 were male. The hearing im-pairment was moderate in 15, severe in 4, and profound in 4. Except for 2 children whose hearing loss was com-bined in 1 ear and sensorineural in the other, all children had bilateral sensorineural hearing loss. Confirmation up to age 3 years occurred in 15 (65%) children, indi-cating that the majority of hearing loss became manifest before this age.

Risk indicators for postnatal hearing loss, as proposed by the JCIH,5 were identified in 11 (48%) children: a

family history of PCHI (3), meningitis (2), craniofacial malformation (2), congenital cytomegaly infection (1), extracorporeal membrane oxygenation (1), persistent pulmonary hypertension (1), and recurrent otitis media with effusion (1). Considering additional occurrences that are not included in the JCIH list but are regarded as risk factors for a hearing loss, the number of children with risk indicators increases by 6 to 17 (74%). The occurrences were ototoxic medication and premature birth (ie, birth before 33rd gestational week). One child was born premature; 3 children were treated with oto-toxic drugs for perinatal sepsis, 1 of whom was also born premature. Two additional children received ototoxic medication, 1 for bacterial infection and 1 for cancer, in the postnatal period. The remaining 6 (26%) of the 23 children showed no risk indicators.

Parental concern about the child’s auditory reactions or speech development prompted the hearing assess-ment in 13 (57%) of the 23 children. In 2 (9%) children,

TABLE 2 Characteristics of 23 Children With Postnatal PCHI

Patient Gender Degree of

Hearing Loss

Age at Confirmation, mo

Risk Indicators Observed Concern About Hearing

Raised by

1 F Moderate 0.9 Meningitis Doctor

2 M Moderate 3.5 关Ototoxic therapy for perinatal sepsis兴 Doctor

3 M Moderate 7.0 Meningitis Doctor

4 F Profound 8.7 Parents

5 M Moderate 11.0 关Birth⬍33rd gestational week兴 Parents

6 M Moderate 11.3 关Birth⬍33rd gestational week, ototoxic therapy兴 Parents

7 M Severe 13.2 Congenital cytomegaly infection Doctor

8 M Profound 15.3 Parents

9 F Moderate 17.6 Doctor

10 M Profound 18.0 Family members with hearing impairment Parents

11 M Moderate 24.9 Parents

12 M Moderate 26.4 关Ototoxic therapy for infection兴 Doctor

13 M Moderate 26.6 Extracorporeal membrane oxygenation Parents

14 M Moderate 33.3 Family members with hearing impairment Parents

15 F Severe 34.4 Parents

16 F Profound 40.8 Persistent pulmonary hypertension Parents

17 M Severe 41.7 Craniofacial malformation Doctor

18 M Moderate 43.0 Recurrent otitis media with effusion Kindergarten teacher

19 M Severe 47.5 关Ototoxic therapy for cancer兴 Parents

20 F Moderate 51.7 Craniofacial malformation Parents

21 M Moderate 55.0 关Ototoxic therapy for perinatal sepsis兴 Kindergarten teacher

22 M Moderate 56.5 Doctor

23 M Moderate 63.2 Family members with hearing impairment Parents


the hearing loss was suspected by a kindergarten teacher, and in 8 (35%) children, it was suspected by a doctor.


Strategies for detecting postnatal hearing impairment are now attracting increased interest,5,12–14 yet little is

known about the number of children who have postna-tal hearing impairment and remain to be detected up to age 1, 2, 3 years, etc, or about the most appropriate means of reliably identifying them. Studies of postnatal hearing loss face the problem that the time of onset of a child’s hearing loss frequently is unknown. Its categori-zation as congenital, perinatal, or postnatal relies on uncertain criteria, eg, the presence of adverse neonatal or postnatal events,7 or the audiologist’s presumption

concerning the time of onset.6 This may be a major

reason for the wide range of prevalence rates of postna-tal PCHI reported so far. The current analysis used a definition of “postnatal” that is not susceptible to this problem. The percentage of postnatal cases among PCHI observed in our sample, 22%, therefore is believed to be better founded than are those that are given in previous studies (despite our awareness of other problems linked to our definition of “postnatal”; see below for a discus-sion). It is interesting that this figure lies somewhere between the percentages reported in the quoted studies, and its confidence interval makes it unlikely that the most extreme estimates of these studies are correct. Con-sidering that the observation period in our study was not a full 9 or 10 years for every birth cohort (as it was previously6–8), the figure of 22% postnatal hearing loss

does not include all cases that manifest up to this age. Thus, a slight upward adjustment of this percentage seems reasonable, leading us to estimate that all postna-tal hearing loss at age 9 years amounts to⬃25%. With this estimate, our study backs the claim that the bulk of childhood hearing loss is congenital and that UNHS plays the leading role in detecting PCHI.

Detection of risk indicators for a postnatal hearing loss was successful in 11 (48%) of 23 children with PCHI for indicators that were drawn from the list proposed by the JCIH.5When additional risk indicators were considered,

namely ototoxic medication and premature birth, this number rose to 17 (74%). The latter indicators, how-ever, were added posthoc (after reviewing the children’s charts), and their validity is doubtful. At any rate, au-diologic monitoring of at-risk children, if practiced with our sample, would have missed at least one quarter of children with hearing impairment as a result of the nonpresence of risk indicators. Still worse, in some of the children, the hearing loss probably manifested after the age of 3 years. If audiologic monitoring had been per-formed only up to this age, as is recommended,5then an

additional portion of the children would have been missed. We are unable to estimate how large this portion

is, because in some children, the hearing loss, despite being confirmed at a later age, could have been present already at age 3 years. Conversely, in our sample, older children were a little underrepresented (as a result of unequal duration of the follow-up of the birth cohorts). Hence, the sample is likely to miss mainly individuals with onset of hearing loss at preschool or school age. Therefore, the number of PCHI cases with onset after age 3 years, as found in our study (approximately one third of the sample), is estimated to provide the lower bound of this portion.

Our findings indicate that continued surveillance of children who are at risk for hearing impairment up to age 3 years, if performed with our sample, would not have been very effective in detecting postnatal hearing loss. Is it an inadequate means for this purpose? We do not think so. We still deem it to be a valuable means of identifying postnatal hearing loss. However, some changes might be useful. For instance, the time frame “up to age 3 years” could be extended, as a considerable number of children will experience the onset of their hearing loss after this age. Findings from the study from the United Kingdom6even suggest that the prevalence of

hearing loss steadily increases up to age 8 or 10 years. Moreover, the list of risk indicators needs validation and completion. Ototoxic drugs are currently not regarded as a risk factor, because, as is argued,5only a small

percent-age of children develop a hearing loss after their admin-istration, yet in our sample, 5 children had received ototoxic substances, and in 3 of them, the diagnosis of hearing loss closely followed the treatment.


combination of a risk indicator surveillance program up to age 3 or 4 years and a hearing screening program in children who enter school would be ideal for promptly detecting postnatal hearing loss.

One of the most delicate prerequisites for the defini-tion of “postnatal” that we applied in our study is a 100% sensitivity of the screen. We are unable to ascer-tain whether our screening program meets this criterion. The sensitivity of a 2-stage screen comparable to ours has been estimated repeatedly to be close to 100%.13–15

However, it is known that the initial phases of program implementation are accompanied by elevated error rates for screening performance.16When we checked this for

our program, we could not find that the portion of postnatal hearing loss was higher in the early periods than in later periods. Therefore, we are confident that the errors that undoubtedly occurred in the beginning have little impact on the results presented here.


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2. Downs MP, Yoshinaga-Itano C. The efficacy of early identifi-cation and intervention for children with hearing impairment. Pediatr Clin North Am.1999;46:79 – 87

3. Moeller M. Early intervention and language development in children who are deaf and hard of hearing.Pediatrics. 2000; 106(3). Available at: www.pediatrics.org/cgi/content/full/106/ 3/e43

4. Yoshinaga-Itano C. Early intervention after universal neonatal hearing screening: impact on outcomes.Ment Retard Dev Disabil Res Rev.2003;9:252–266

5. Joint Committee on Infant Hearing. Year 2000 position statement: principles and guidelines for early hearing detection and intervention programs.Pediatrics.2000;106:798 – 817 6. Fortnum H, Summerfield Q, Marshall D, Davis A, Bamford J.

Prevalence of permanent childhood hearing impairment in the United Kingdom and implications for universal neonatal hear-ing screenhear-ing: questionnaire based ascertainment study.BMJ. 2001;323:536 –539

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hearing impairment in the Trent Region, 1985–1993. Br J Audiol.1997;31:409 – 446

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DOI: 10.1542/peds.2005-1455



Viktor Weichbold, Doris Nekahm-Heis and Kunigunde Welzl-Mueller

Universal Newborn Hearing Screening and Postnatal Hearing Loss


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DOI: 10.1542/peds.2005-1455



Viktor Weichbold, Doris Nekahm-Heis and Kunigunde Welzl-Mueller

Universal Newborn Hearing Screening and Postnatal Hearing Loss


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TABLE 1Studies That Included Information on the Prevalence of Postnatal Hearing Loss
TABLE 2Characteristics of 23 Children With Postnatal PCHI


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