Levels of evidence: universal newborn hearing screening (UNHS) and early hearing detection and intervention systems

Abstract Levels of evidence differ according to the audience addressed. Implementation of universal newborn hearing screening requires responses to a complex myriad of diverse groups: the general public, families with children who are deaf or hard of hearing, the deaf and hard of hearing communities, hospital administrators, physicians (pediatricians, general practitioners, ear nose and throat physicians, geneticists), managed care, Medicaid, insurance agencies, and politicians. The level of evidence required by medical/health agencies and task forces may differ from the levels of evidence available in education and intervention. Issues related to the low incidence of the disability, the lack of a normal distribution within the disability study, the obstacles to random assignment to treatment, and designs that include a control group with ''no treatment'' have implications legally and ethically for the professional providing services to families and children who are deaf or hard of hearing. This session will discuss issues related to ''convenience samples,'' number of subjects included in research studies, and the population required to obtain a large enough sample of children with low-incidence disabilities. The level of evidence required to demonstrate sensitive periods of development, which are a critical element for justification of implementing a universal newborn hearing screening includes both behavioral and neurological information. Sensitive periods may have different duration for different aspects of development, such as social-emotional development, auditory and speech development, or language development. Further complicating the question of sensitive periods of development are the distinct possibility that different sensitive periods exist for development of age-level vocabulary, for establishing English phonology, or for mastering English syntax. Research outcomes provide evidence that age of identification of hearing loss is reduced, that age of intervention initiation is lowered, and that the outcomes of intervention are better because of the establishment of a screening program. Most professionals in communication disorders believe that screening is not the actual cause of better developmental outcomes but that the age when children begin to have access to language and communication and the characteristics of th

Effectiveness of universal newborn hearing screening: A systematic review and meta-analysis

Background: Permanent bilateral hearing loss (PBHL) is a serious condition in newborns, with a prevalence of at least one per 1000 live births. However, there has been no recent systematic review and meta-analysis of the effectiveness of universal newborn hearing screening programs (UNHS). Methods: We registered our study protocol on PROSPERO CRD42020175451. Primary outcomes were any identification of PBHL (ie, PBHL diagnosed at any time), age of identification of PBHL, and neurodevelopment. Two reviewers searched standard databases to March 2022 and extracted data. We used fixed and random effects meta-analysis to pool data and graded the certainty of evidence using standard methods. Results: The search retrieved 2834 records. We identified five studies reporting on the effects of UNHS vs no UNHS in 1 023 610 newborns. The relative risk of being identified with PBHL before nine months in infants with UNHS compared to infants without UNHS was 3.28 (95 % confidence interval (95 % CI) = 1.84, 5.85, one study, 1 023 497 newborns, low certainty evidence). The mean difference in the age of identification of PBHL in infants with UNHS compared to infants without UNHS was 13.2 months earlier (95 % CI = -26.3, -0.01, two studies, 197 newborns, very low certainty evidence). The relative risk of infants eventually being identified with PBHL in infants with UNHS compared to infants without UNHS was 1.01 (95 % CI = 0.89, 1.14, three studies, 1 023 497 newborns, low certainty evidence). At the latest follow-up at 3-8 years, the standardised mean difference (SMD) in receptive language development between infants with UNHS compared to infants without UNHS was 0.60 z scores (95 % CI = 0.07, 1.13, one study, 101 children, low certainty evidence) and the mean difference in developmental quotients was 7.72 (95 % CI = -0.03, 15.47, three studies, 334 children, very low certainty evidence). The SMD in expressive language development was 0.39 z scores (95 % CI = -0.20, 0.97, one study, 87 children, low certainty evidence) and the mean difference in developmental quotients was 10.10 scores (95 % CI = 1.47, 18.73, 3 studies, 334 children, very low certainty evidence). Conclusions: UNHS programs result in earlier identification of PBHL and may improve neurodevelopment. UNHS should be implemented across high-, middle-, and low-income countrie

Spectral-temporal EEG dynamics of speech discrimination processing in infants during sleep

BACKGROUND: Oddball paradigms are frequently used to study auditory discrimination by comparing event-related potential (ERP) responses from a standard, high probability sound and to a deviant, low probability sound. Previous research has established that such paradigms, such as the mismatch response or mismatch negativity, are useful for examining auditory processes in young children and infants across various sleep and attention states. The extent to which oddball ERP responses may reflect subtle discrimination effects, such as speech discrimination, is largely unknown, especially in infants that have not yet acquired speech and language. RESULTS: Mismatch responses for three contrasts (non-speech, vowel, and consonant) were computed as a spectral-temporal probability function in 24 infants, and analyzed at the group level by a modified multidimensional scaling. Immediately following an onset gamma response (30-50 Hz), the emergence of a beta oscillation (12-30 Hz) was temporally coupled with a lower frequency theta oscillation (2-8 Hz). The spectral-temporal probability of this coupling effect relative to a subsequent theta modulation corresponds with discrimination difficulty for non-speech, vowel, and consonant contrast features. DISCUSSION: The theta modulation effect suggests that unexpected sounds are encoded as a probabilistic measure of surprise. These results support the notion that auditory discrimination is driven by the development of brain networks for predictive processing, and can be measured in infants during sleep. The results presented here have implications for the interpretation of discrimination as a probabilistic process, and may provide a basis for the development of single-subject and single-trial classification in a clinically useful context. CONCLUSION: An infant's brain is processing information about the environment and performing computations, even during sleep. These computations reflect subtle differences in acoustic feature processing that are necessary for language-learning. Results from this study suggest that brain responses to deviant sounds in an oddball paradigm follow a cascade of oscillatory modulations. This cascade begins with a gamma response that later emerges as a beta synchronization, which is temporally coupled with a theta modulation, and followed by a second, subsequent theta modulation. The difference in frequency and timing of the theta modulations appears to reflect a measure of surprise. These insights into the neurophysiological mechanisms of auditory discrimination provide a basis for exploring the clinically utility of the MM

Use of the LENA Autism Screen with Children who are Deaf or Hard of Hearing

Background and Objectives: This systematic review reports the evidence from the literature concerning the potential for using an automated vocal analysis, the Language ENvironment Analysis (LENA, LENA Research Foundation, Boulder, CO, USA) in the screening process for children at risk for autism spectrum disorder (ASD) and deaf or hard of hearing (D/HH). ASD and D/HH have increased comorbidity, but current behavioral diagnostic and screening tools have limitations. The LENA Language Autism Screen (LLAS) may offer an additional tool to disambiguate ASD from D/HH in young children. Materials and Methods: We examine empirical reports that use automatic vocal analysis methods to differentiate disordered from typically developing children. Results: Consensus across the sampled scientific literature shows support for use of automatic methods for screening and disambiguation of children with ASD and D/HH. There is some evidence of vocal differentiation between ASD, D/HH, and typically-developing children warranting use of the LLAS, but additional empirical evidence is needed to better understand the strengths and weaknesses of the tool. Conclusions: The findings reported here warrant further, more substantive, methodologically-sound research that is fully powered to show a reliable difference. Findings may be useful for both clinicians and researchers in better identification and understanding of communication disorders

Infants and Toddlers with Hearing Loss from Bilingual Homes

This article provides information about intervention strategies for children who are deaf or hard of hearing in non-English speaking homes with research data on children in Spanish-speaking homes living in the United States.  A description of the language learning environment of these families are compared to children with typical development in Spanish-speaking homes, children who are deaf or hard of hearing in English-speaking homes and children with typical development in English-speaking homes.  The language learning environment includes the average number of adult words, of conversational turns, and child vocalizations in an average day, as well as the percent of the day in silence, in noise, with TV/radio, with distant language and meaningful language. </p

Outcomes of Universal Newborn Screening Programs: Systematic Review

Background: This systematic review examined the outcomes (age of identification and intervention, developmental outcomes, cost-effectiveness, and adverse effects on parents) of universal newborn hearing screening (UNHS) for children with permanent congenital hearing loss (PCHL). Materials and methods: Multiple electronic databases were interrogated in March and April 2020 with further reports identified from article citations and unpublished literature. UNHS reports in English with comparisons of outcomes of infants who were not screened, and infants identified through other hearing screening programs. Results: 30 eligible reports from 14 populations with 7,325,138 infants screened through UNHS from 1616 non-duplicate references were included. UNHS results in a lower age of identification, amplification, and the initiation of early intervention services and better language/literacy development. Better speech perception/production were shown in younger, but not in older, children with early identification after UNHS. No significant findings were found for behavior problems and quality of life. UNHS was found to be cost-effective in terms of savings to society. In addition, no significant parental harm was noted as a result of UNHS. Conclusions: In highly developed countries, significantly better outcomes were found for children identified early through UNHS programs. Early language development predicts later literacy and language development

Speech Discrimination in Infancy Predicts Language Outcomes at 30 Months for Both Children with Normal Hearing and Those with Hearing Differences

Background: Speech discrimination assessments are used to validate amplification fittings of older children who are hard of hearing (CHH). Unfortunately, speech discrimination is not assessed clinically ≤24 months and in turn no studies have investigated the relationship between speech discrimination during infancy and later language development among CHH. Objective: To examine the relationship between an individual infant’s speech discrimination measured at 9 months and their expressive/receptive spoken language at 30 months for children with normal hearing (CNH) and CHH. Methods: Behavioral speech discrimination was assessed at 9 months and language assessments were conducted at 16, 24, and 30 months using a parent questionnaire, and at 30 months using the Mullen Scales of Early Learning among 90 infants (49 CNH; 41 CHH). Results: Conditioned Head Turn (CHT) performance for /a-i/ significantly predicted expressive and receptive language at 30 months across both groups. Parental questionnaires were also predictive of later language ability. No significant differences in speech discrimination or language outcomes between CNH and CHH were found. Conclusions: This is the first study to document a positive relationship between infant speech discrimination and later language abilities in both early-identified CHH and CNH

Frequency of Early Intervention Sessions and Vocabulary Skills in Children with Hearing Loss

Background: A primary goal of early intervention is to assist children in achieving age-appropriate language skills. The amount of intervention a child receives is ideally based on his or her individual needs, yet it is unclear if language ability impacts amount of intervention and/or if an increased frequency of intervention sessions results in better outcomes. The purpose of this study was to determine the relationship between the frequency of early intervention sessions and vocabulary outcomes in young children with hearing loss. Methods: This was a longitudinal study of 210 children 9 to 36 months of age with bilateral hearing loss living in 12 different states. Expressive vocabulary skills were evaluated using the MacArthur–Bates Communicative Development Inventories. Results: A higher number of intervention sessions reported at the first assessment predicted better vocabulary scores at the second assessment, and more sessions reported at the second assessment predicted better scores at the third assessment. For each increase in the number of sessions reported, there was a corresponding, positive increase in vocabulary quotient. In contrast, children’s vocabulary ability at an earlier time point did not predict intervention session frequency at a later point in time. Conclusions: A significant prospective effect was apparent with more therapy sessions resulting in improved vocabulary scores 9 months later. These findings underscore the importance of early intervention. Pediatricians and other health care professionals can help apply these findings by counseling parents regarding the value of frequent and consistent participation in early intervention

Do acoustic environment characteristics affect the lexical development of children with CIs? A longitudinal study before and after CI activation

Purpose: The present study investigates the acoustic environment of children with cochlear implants (CIs) and the relationship between exposure to speech, in noise and in quiet, and the children\u2019s lexical production up to one year after CI activation, while controlling for the effect of early individual differences in receptive vocabulary growth. Method: Eighteen children with CIs were observed at three, six, and 12 months after CI activation. Children's spontaneous words production during interaction with their mothers (types and tokens) and their expressive and receptive vocabulary size were considered. The characteristics of the acoustic environments in terms of acoustic scenes (speech in noise or in quiet, quiet, noise, music, and other) and of loudness ranges were assessed using data logging of the children's devices. Results: Data analysis showed that both the number of tokens and the number of types produced one year after CI activation were affected by the children\u2019s exposure to speech in quiet with a loudness range between 40 and 69 dB. Expressive vocabulary size and types were affected by the receptive vocabulary knowledge that the children achieved over the first three months after CI activation. Conclusions: Our data support the role of speech environment and individual differences in early comprehension on lexical production. The importance of exposure to speech with particular characteristics for the lexical development of children with CIs and the implications for clinical practice are discussed