Determining cochlear implant candidacy in children with residual hearing: A scoping review.

OBJECTIVES: The purpose of this review was to summarize what is known about criteria, assessments, and recommendations for evaluating cochlear implant (CI) candidacy in children with residual hearing. METHODS: Peer-reviewed studies were identified through a systematic search in five electronic databases. Articles were screened and assessed for eligibility. From the eligible studies, data were extracted to summarize and present a narrative synthesis of the findings. RESULTS: A total of seven articles (two reviews and five primary studies) were included in the final analysis. Hearing levels better than the moderately severe to severe range (65-90 dB HL) tend to be supported as audiological candidacy criteria for pediatric CI. Recommendations for candidacy consideration based on audiologic thresholds range from 65 to 80 dB Hl pure-tone average as the lower boundary. Our review did not identify any specific assessment protocols. However, additional decision-making considerations related to borderline hearing loss configurations and assessment tools (the Speech Intelligibility Index and the Pediatric Minimum Speech Test Battery) were identified. Supplementary assessment considerations were also reported. CONCLUSION: There is limited information regarding specific assessment protocols for children with residual hearing. The literature is primarily focused on guidelines related to audiologic criteria, although it is widely recommended that other areas of functioning should also be considered. Most recommendations appear to be based on expert opinion, clinical expertise, and evidence from overall pediatric CI outcomes rather than empirical evidence targeting children with residual hearing. There is an ongoing need for research to further develop protocols and tools that can assist clinicians and families in making cochlear implantation decisions for children with residual hearing.

An Umbrella Review of Cochlear Implant Outcomes in Children With Auditory Neuropathy.

PURPOSE: The objective of this overview of systematic reviews (SRs; umbrella review) was to systematically summarize and critically appraise current evidence of cochlear implant (CI) outcomes in children with auditory neuropathy spectrum disorder (ANSD). METHOD: This study was guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 statement. The methodological quality and the risk of bias in the included SRs were assessed using A MeaSurement Tool to Assess systematic Reviews 2 checklist and the Risk of Bias in Systematic Reviews tool, respectively. RESULTS: According to eight included SRs, children with ANSD achieve CI outcomes (speech perception performance) similar to their peers with sensorineural hearing loss. In children with postsynaptic ANSD (cochlear nerve deficiency), cochlear nerve hypoplasia is associated with better speech recognition outcomes compared with cochlear nerve aplasia, especially in the absence of additional disabilities. Except for one study, the overall quality of the included SRs was critically low, and except for three studies, evidence of a high risk of bias was identified in other included SRs. CONCLUSIONS: Current evidence supports CI benefits for children with ANSD. To improve the quality of evidence, well-designed, prospective studies with appropriate sample sizes, using valid outcome measures, clarifying matching criteria, and taking into account the role of confounding factors are essential.

Cochlear implant decision-making for children with residual hearing: Perspectives of parents.

PURPOSE: Cochlear implant (CI) decision-making is particularly challenging for families of children who have residual hearing. Parents of these children may be uncertain about whether the potential benefits of CIs outweigh the risks. This study aimed to understand parents' decisional needs during the decision-making process for children with residual hearing. METHOD: Semi-structured interviews were conducted with parents of 11 children who had received CIs. Open-ended questions were asked to encourage parents to share their experiences about the decision-making process, their values/preferences, and their needs. The interviews were transcribed verbatim and analyzed using thematic analysis. RESULTS: Data were organized according to three key themes: (1) Parents' decisional conflict, (2) values and preferences, (3) decision support and parents' needs. We found that overall parents were satisfied with their decision-making process and the decision support from practitioners. However, parents stressed the importance of receiving more personalized information that considers their specific concerns, values and preferences related to family's circumstances. CONCLUSIONS: Our research provides additional evidence to guide the CI decision-making process for children with residual hearing. Additional collaborative research with audiology and decision-making experts specifically on facilitating shared decision-making is needed to provide better decision coaching for these families.

Long-term follow-up of children with hearing loss that is minimally progressive.

OBJECTIVES: The purpose of this study was to describe changes in audiometric thresholds over time in children whose hearing loss demonstrated early mild progression. DESIGN: This was a retrospective follow-up study to examine long-term audiologic results in children with progressive loss. STUDY SAMPLE: We examined audiologic data for 69 children, (diagnosed from 2003 to 2013), who had been previously categorised as having "minimal" progressive hearing loss. RESULTS: Children had a median of 10.0 (7.5, 12.1) years of follow-up and a median age of 12.5 (IQR: 11.0, 14.5) years; 92.8%; 64 of 69) of children continued to show progressive hearing loss (defined as a decrease of ≥10 dB at two or more adjacent frequencies between 0.5 and 4 kHz or a decrease in 15 dB at one frequency) in at least one ear since diagnosis. Further examination showed that 82.8% of ears (106 of 128) had deterioration in hearing. Of the 64 children, 29.7% (19/64) showed further deterioration since the first analysis. CONCLUSION: More than 90% of children identified as having minimal progressive hearing loss continued to show deterioration in hearing. Ongoing audiological monitoring of children with hearing loss is indicated to ensure timely intervention and to better counsel families.

Trajectory of hearing loss in children with unilateral hearing loss.

Introduction: The aim of this study was to quantify the amount of deterioration in hearing and to document the trajectory of hearing loss in early identified children with unilateral hearing loss (UHL). We also examined whether clinical characteristics were associated with the likelihood of having progressive hearing loss. Methods: As part of the Mild and Unilateral Hearing Loss Study, we followed a population-based cohort of 177 children diagnosed with UHL from 2003 to 2018. We applied linear mixed models to examine hearing trends over time including the average amount of change in hearing. Logistic regression models were used to examine the relationship between age and severity at diagnosis, etiology, and the likelihood of progressive loss and amount of deterioration in hearing. Results: The median age of the children at diagnosis was 4.1 months (IQR 2.1, 53.9) and follow-up time was 58.9 months (35.6, 92.0). Average hearing loss in the impaired ear was 58.8 dB HL (SD 28.5). Over the 16-year period, 47.5% (84/177) of children showed deterioration in hearing in one or both ears from their initial diagnostic assessment to most recent assessment including 21 (11.9%) who developed bilateral hearing loss. Average deterioration in the impaired ear ranged from 27 to 31 dB with little variation across frequencies. Deterioration resulted in a change in category of severity for 67.5% (52/77) of the children. Analysis for children who were followed for at least 8 years showed that most lost a significant amount of hearing rapidly in the first 4 years, with the decrease stabilizing and showing a plateau in the last 4 years. Age and severity at diagnosis were not significantly associated with progressive/stable loss after adjusting for time since diagnosis. Etiologic factors (ENT external/middle ear anomalies, inner ear anomalies, syndromic hearing loss, hereditary/genetic) were found to be positively associated with stable hearing loss. Conclusion: Almost half of children with UHL are at risk for deterioration in hearing in one or both ears. Most deterioration occurs within the first 4 years following diagnosis. Most children did not experience sudden "large" drops in hearing but more gradual decrease over time. These results suggest that careful monitoring of UHL especially in the early years is important to ensure optimal benefit from early hearing loss detection.

Cochlear Implant Decision Making for Children With Residual Hearing: Perspectives of Practitioners.

PURPOSE: Cochlear implants (CIs) are increasingly considered for children with residual hearing who benefit from hearing aids (HAs). However, the decision-making process for families of these children and for practitioners is particularly challenging because there is no clear audiological cut point for CI candidacy. This study aimed to understand Canadian practitioners' perspectives of the CI decision-making process and how they guide families of children with residual hearing. METHOD: Semistructured interviews were conducted with a total of 17 practitioners through four focus groups and one individual interview. Interviews were transcribed verbatim, and a thematic analysis was carried out. RESULTS: Data were organized into five broad domains: candidacy issues for children with residual hearing, practitioners' roles in decision support, additional considerations affecting decision making, factors facilitating decision making, and practitioners' needs. CONCLUSIONS: This study found that practitioners' confidence in determining candidacy and supporting parents has increased due to their experiences with positive outcomes for these children. Practitioners indicated that there was a need for more research to guide the decision-making process.

Benefits and risks related to cochlear implantation for children with residual hearing: a systematic review.

OBJECTIVE: This study aimed to synthesise information concerning the potential benefits and risks related to cochlear implants (CIs) versus hearing aids (HAs) in children with residual hearing. DESIGN: A systematic review of articles published from January 2003 to January 2019 was conducted. STUDY SAMPLE: Our review included studies that compared the benefits and risks of CIs versus HAs in children (≤18 years old) with residual hearing. A total of 3265 citations were identified; 8 studies met inclusion criteria. RESULTS: Children with CIs showed significantly better speech perception scores post-CI than pre-CI. There was limited evidence related to improvement in everyday auditory performance, and the results showed non-significant improvement in speech intelligibility. One study on social-emotional functioning suggested benefits from CIs. In four studies, 37.2% (16/43) of children showed loss of residual hearing and 14.0% (8/57) had discontinued or limited use of their device. CONCLUSIONS: Children with CIs showed improvement in speech perception outcomes compared to those with HAs. However, due to the limited number of studies and information to guide decision-making related to other areas of development, it will be important to conduct further research of both benefits and risks of CIs in this specific population to facilitate decision-making.

Parent-Reported Stress and Child Behavior for 4-Year-Old Children with Unilateral or Mild Bilateral Hearing Loss.

Children with unilateral or mild bilateral hearing loss are increasingly identified in early childhood. Relatively little is known about how hearing loss affects their developmental trajectory or whether it contributes to parenting stress for these parents. This study aimed to examine child behavior and parenting stress in parents of children with unilateral/mild bilateral hearing loss compared to children with typical hearing. This prospective study involved 54 children with unilateral/mild bilateral hearing loss identified at a median age of 4.5 months (IQR 2.6, 6.5) and 42 children with typical hearing. At age 48 months, child behavior and parenting stress were measured. Auditory and language results were also analyzed in relation to child behavior and parenting stress. Parents of these children did not report significantly more parenting stress or behavior problems than parents of children with typical hearing. However, both parenting stress and child behavior were related to functional hearing in noise.

Benefits of auditory-verbal intervention for adult cochlear implant users: perspectives of users and their coaches.

OBJECTIVE: Post-implant rehabilitation is limited for adult cochlear implant (CI) recipients. The objective of this research was to capture the perspectives of CI users and their coaches regarding their experiences with auditory-verbal intervention as an example of post-implant rehabilitation and their views on perceived benefits and challenges related to the intervention. DESIGN: This qualitative study involved semi-structured focus group interviews with adult CI users and their coaches who accompanied them in a 24-week auditory-verbal intervention program. STUDY SAMPLE: A total of 17 participants (eight CI users and nine coaches) contributed to the interviews. RESULTS: Three key topic areas emerged from the interviews capturing CI users' and coaches' experiences related to the intervention program: (1) benefits of the intervention, (2) factors affecting experiences, and (3) challenges and barriers. Benefits included increased confidence in hearing, communication, social participation, and new knowledge about technology and hearing. Factors affecting the experience were participants' motivation and the therapist's skills. The primary challenge was the time commitment for weekly therapy. CONCLUSIONS: Both CI users and coaches perceived a focussed auditory-verbal intervention to be beneficial in improving speech understanding, confidence in using hearing, social interaction, and knowledge about technology. Participants recommended reducing the intensity of intervention to facilitate participation.

Paediatric hearing aid use: a systematic review.

CONTEXT: Hearing loss (HL) is one of the most common disorders present at birth. Parents' management of their child's hearing aids (HAs) and regular follow-up with healthcare providers HA are fundamental components of effective intervention. OBJECTIVE: The primary objective of this systematic review was to synthesise the current literature on HA use in the paediatric population, and the secondary objective was to review the factors associated with HA use. METHODS: Electronic databases, including MEDLINE, EMBASE, CINAHL, and LLBA from 2005 to 2019, were searched. Two reviewers individually screened potentially relevant articles over two phases. RESULTS: Fifteen studies met this review criteria. Four studies reported HA use based on data logging records. In nine studies, the amount of HA use was evaluated based on parents' reports, and three studies concluded that parents overestimate their child's HA use. Age, degree of HL and parents' education level were the most frequently reported factors associated with a child's amount of HA use. CONCLUSIONS: The results of this review will provide a foundation for future studies on the importance of monitoring HA use and the impact of consistent HA use on the language development of children with HL.

Clinical characteristics and outcomes of children with cochlear implants who had preoperative residual hearing.

OBJECTIVE: Cochlear implants (CI) candidacy criteria have expanded to include children with more residual hearing. This study explored the clinical profiles and outcomes of children with CIs who had preoperative residual hearing in at least one ear. DESIGN: A retrospective chart review was conducted to collect clinical characteristics and speech perception data. Pre- and post-CI auditory and speech perception data were analysed using a modified version of the Pediatric Ranked Order Speech Perception (PROSPER) score. STUDY SAMPLE: This study included all children with residual hearing who received CIs in one Canadian paediatric centre from 1992 to 2018. RESULTS: A total of 100 of 389 (25.7%) children with CIs had residual hearing (median 77.6 dB HL, better ear). The proportion of children with residual hearing increased from 1992 to 2018. Children who had auditory behaviour and speech perception tests (n = 83) showed higher modified PROSPER scores post-CI compared to pre-CI. Phonologically Balanced Kindergarten (PBK) test scores were available for 71 children post-CI; 81.7% (58/71) of children achieved > 80% on the PBK. CONCLUSIONS: One in four children who received CIs had residual hearing, and most of them had severe hearing loss at pre-CI. These children showed a high level of speech perception with CIs.

Social communication and quality of life in children using hearing aids.

OBJECTIVES: This study compared the parent-reported structural language and social communication skills-measured with the Children's Communication Checklist-2 (CCC-2)-and health-related quality of life (HR-QOL)-measured with the Pediatric Quality of Life Inventory (PedsQL)-of children who use hearing aids (HAs) and their typical-hearing (TH) peers. DESIGN: The participants were 88 children (age range of 5; 6 to 13; 1 (years; months)) and their parents: 45 children with bilateral moderate to severe hearing loss using HAs who had no additional disabilities and 43 children with typical hearing. The groups were matched based on chronological age, gender, nonverbal IQ, and parental education level. The parents completed questionnaires related to their children's communication skills, including subdomains structural language and social communication, and HR-QOL. RESULTS: The HA group had significantly poorer overall communication skills than the TH group (r = 0.49). The children in the HA group scored significantly lower than the TH group on both structural language (r = 0.37) and social communication (r = 0.41). Half of the children in the HA group had overall communication scores that either indicated concern or required further investigation according to the instrument's manual. In terms of psychosocial functioning, which was measured as HR-QOL, the subdomain school functioning was the main driver of the difference between groups, with the HA group being at least twice as likely (OR = 2.52) as the TH group to have poor HR-QOL in the school domain. Better parent-reported social communication was associated with better parent-reported psychosocial functioning in the children using HAs-even when background variables were taken into account. CONCLUSION: The results suggest that traditional assessments and interventions targeting structural aspects of language may overlook social communication difficulties in children with HAs, even those with no additional disabilities. As school functioning stood out as the most problematic domain for children with HAs, efforts to improve the well-being of these children should focus on this area.

Coaching Caregivers of Children who are Deaf or Hard of Hearing: A Scoping Review.

Caregiver coaching is an expected practice in early intervention. However, little is known about coaching with caregivers of children who are deaf or hard of hearing, receiving services for listening and spoken language (LSL). A systematic review of 7 databases, the gray literature, and consultation with 7 expert LSL practitioners yielded 506 records for full-text review, 22 of which were ultimately included in the review. Our findings are presented as 3 themes: coaching practices, training for coaching, and effectiveness of coaching. Eight models of coaching were identified in the literature, from which we identified commonalities to propose a consolidated model that illustrates the recommendations and process of caregiver coaching found in the LSL literature.

Cytomegalovirus-A Risk Factor for Childhood Hearing Loss: A Systematic Review.

OBJECTIVE: Permanent hearing loss is an important public health issue in children with consequences for language, social, and academic functioning. Early hearing detection, intervention, and monitoring are important in mitigating the impact of permanent childhood hearing loss. Congenital cytomegalovirus (CMV) infection is a leading cause of hearing loss. The purpose of this review was to synthesize the evidence on the association between CMV infection and permanent childhood hearing loss. DESIGN: We performed a systematic review and examined scientific literature from the following databases: MEDLINE, Ovid MEDLINE(R) Daily and Ovid MEDLINE(R), Embase, and CINAHL. The primary outcome was permanent bilateral or unilateral hearing loss with congenital onset or onset during childhood (birth to 18 years). The secondary outcome was progressive hearing loss. We included studies reporting data on CMV infection. Randomized controlled trials, quasi-experimental studies, nonrandomized comparative and noncomparative studies, and case series were considered. Data were extracted and the quality of individual studies was assessed with the Qualitative Assessment Tool for Quantitative Studies (McMaster University). The quality and strength of the evidence were graded using the Grading of Recommendations Assessment, Development and Evaluation (GRADE). A narrative synthesis was completed. RESULTS: Sixty-five articles were included in the review. Prevalence of hearing loss at birth was over 33% among symptomatic CMV-infected newborns and less than 15% in asymptomatic infections. This difference in prevalence was maintained during childhood with more than 40% prevalence reported for symptomatic and less than 30% for asymptomatic CMV. Late-onset and progressive hearing loss appear to be characteristic of congenital CMV infections. Definitions of hearing loss, degree of loss, and reporting of laterality varied across studies. All degrees and both bilateral and unilateral loss were reported, regardless of symptomatic and asymptomatic status at birth, and no conclusions about the characteristics of hearing loss could be drawn. Various patterns of hearing loss were reported including stable, progressive, and fluctuating, and improvement in hearing (sometimes to normal hearing) was documented. These changes were reported in children with symptomatic/asymptomatic congenital CMV infection, presenting with congenital/early onset/late-onset hearing loss and in children treated and untreated with antiviral medication. CONCLUSIONS: Symptomatic and asymptomatic congenital CMV infection should be considered a risk factor for hearing loss at birth and during childhood and for progressive hearing loss. Therefore, CMV should be included as a risk factor in screening and surveillance programs and be taken into account in clinical follow-up of children with hearing loss.

Hearing loss prevalence and hearing health among school-aged children in the Canadian Arctic.

OBJECTIVE: Hearing loss is an important health concern in Canada's Arctic. The objective of this research was to provide information on the prevalence of childhood hearing loss in Nunavut. DESIGN: This cross-sectional study involved comprehensive audiologic assessments of school-aged children in six communities to determine overall and community-specific prevalence of hearing loss. Data were collected about hearing aid use and factors affecting use through a parent questionnaire. STUDY SAMPLE: Assessments were completed for 644 children in kindergarten to grade 6. RESULTS: 124 (19.3%) children had hearing loss of ≥ 30 dB HL at one or more frequencies in at least one ear (93.5% conductive loss). Applying a Canadian prevalence study definition, 148 (23.5%) children had hearing loss. Tympanic membrane perforations were present in 36.8% (n = 28) of children with unilateral and 45.8% (n = 22) with bilateral loss. CONCLUSIONS: The prevalence of hearing loss in Canada's North was almost three times that reported for non-indigenous children. One in five school-aged children was found to have hearing loss that is likely to affect classroom learning and social/emotional development. A hearing health strategy tailored to this population is critically needed.

Progressive Hearing Loss in Children With Mild Bilateral Hearing Loss.

Purpose This study investigated progressive hearing loss in a cohort of children who were identified with permanent mild bilateral hearing loss. Method This population-based study included 207 children with permanent mild bilateral hearing loss, diagnosed and followed from 2003 to 2016 in 1 region of Canada. Clinical characteristics and initial audiologic results were collected prospectively at diagnosis, and audiologic information was updated. Changes in hearing levels between the 1st and most recent assessment were analyzed to determine progressive hearing loss. Clinical characteristics were compared between children with progressive and stable hearing loss. The association between risk indicators and progressive hearing loss was explored through logistic regression. Results A total of 47.4% (94 of 207) had progressive hearing loss in at least 1 ear, and 50% (47 of 94) of those experienced more than 20-dB average drop in thresholds. For these 94 children, a total of 147 ears were affected, and 116 (78.9%) ears experienced sufficient change in thresholds to be coded as a worse category of hearing loss. In the subset of 85 children with more than 5 years of audiologic follow-up, 56.4% (53/85) showed a decrease in hearing. Of the total sample of 207 children, 137 (66.2%) continued to have mild hearing loss in the better ear. There was no association between the risk factors examined (family history of hearing loss, admission to the neonatal intensive care unit, or presence of a syndrome) and progressive hearing loss. Conclusion This study found that almost half of children with mild bilateral hearing loss showed a decrease in hearing in at least 1 ear. One third of the children first diagnosed with mild hearing loss in the better ear now have moderate or worse hearing loss in both ears. These findings point to the importance of careful long-term monitoring of children who present with mild hearing loss.

Auditory, Social, and Behavioral Skills of Children With Unilateral/Mild Hearing Loss.

This study explored the impact of mild bilateral or unilateral hearing loss on auditory, social, and behavior skills in early school-aged children. Thirty-two children (aged 5-9 years) were evaluated with parent and teacher questionnaires. Most outcomes were within the range of expected scores. However, functional auditory skills were below published results for children with typical hearing. On the social skills scale, about 21.4% (parent-reported) and 20.0% (teacher-reported) of children were below one standard deviation (SD) of the normative mean (i.e., a standard score below 85). On the parent-reported behavior test, over a quarter of children scored beyond 1 SD on some subscales. Laterality of hearing loss had no effect on outcomes (p > .05). Agreement between parents and teachers varied from poor (intraclass correlation coefficient [ICC]: .162) to moderate (ICC: .448). Results indicate that these children are functioning in most areas like their peers with typical hearing. Additional research on this population of children who may benefit from early identification and amplification is warranted.

Candidacy for Amplification in Children With Hearing Loss: A Review of Guidelines and Recommendations.

Purpose The 1st point in the intervention process for the majority of children is the fitting of hearing devices. The objective of this review was to compile guidelines and recommendations for candidacy criteria for children with hearing loss. Method Electronic databases (e.g., MEDLINE, Embase, and Cumulative Index of Nursing and Allied Health Literature) and websites were searched. Any document referring to children with hearing loss that discussed amplification guidelines or protocols was included. Documents specific to implantable devices or addressing only remote microphone systems were excluded. One reviewer screened all potentially relevant documents, and a subset was screened by a 2nd reviewer. Guidelines/recommendations referring to pediatric amplification candidacy were extracted. Results A total of 40 documents were included for data extraction. Studies were categorized according to hearing loss of any degree, with separate categories for documents providing specific criteria for mild bilateral, unilateral, and auditory neuropathy spectrum disorders. Guidelines ranged from generic statements about the need for amplification to criteria based on specific audiometric thresholds. In guidelines recommending audiometric cut-points, the majority considered > 25 dB HL as a criterion for consideration for amplification. Overall, guidelines for children with mild bilateral and unilateral loss remain more ambiguous, and there was some variation across the recommendations. Guidelines for auditory neuropathy spectrum disorder stressed the need to obtain results from behavioral audiometry before considering amplification. Conclusions Numerous organizations have established candidacy guidelines for pediatric amplification. Most guidelines specify criteria for amplification as audiometric threshold levels. There is considerable variation in the guidelines for mild bilateral and unilateral hearing loss with candidacy criteria ranging from 15 to 30 dB HL, and many guidelines recommend a case-by-case decision approach.

Risk factors for hearing loss in children: a systematic literature review and meta-analysis protocol.

BACKGROUND: Hearing loss in newborns and children is a public health concern, due to high prevalence and negative effects on their development. Early detection and intervention of childhood hearing loss may mitigate these negative effects. Population-based newborn hearing screening programs have been established worldwide to identify children at risk for congenital hearing loss and to follow children at risk for late onset or progressive hearing loss. This article presents the protocol for a systematic review that aims to review the risk factors associated with permanent hearing loss in children, including congenital, early, or late onset. Risk factors associated with progressive hearing loss will be investigated as a secondary aim. METHODS: Scientific literature from the following databases will be investigated: MEDLINE, Ovid MEDLINE(R) Daily and Ovid MEDLINE(R), Embase, and CINAHL. The primary outcome is a permanent bilateral or unilateral hearing loss with congenital onset or onset during childhood (birth to 18 years). The secondary outcome is progressive hearing loss. Studies must report data on risk factors associated with permanent hearing loss; risk factors may be present at birth or later and result in immediate or delayed hearing loss. Randomized controlled trials, quasi-experimental studies, nonrandomized comparative and non-comparative studies, and case series will be included. The risk of bias will be assessed using the Qualitative Assessment Tool for Quantitative Studies (McMaster University). If aggregation of data is possible for a subsection of studies, we will pool data using meta-analysis techniques. If aggregation of data is not possible, a qualitative synthesis will be presented. We will assess the quality and strength of the overall body of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE). The systematic review follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations. DISCUSSION: The resulting information will inform the update of a provincial audiological surveillance protocol for the Ontario Infant Hearing Program and will be applicable to early hearing detection and intervention (EHDI) programs worldwide. SYSTEMATIC REVIEW REGISTRATION: We have registered the protocol in the International Prospective Register of Systematic Reviews (PROSPERO), registration number CRD42018104121.