A systematic scoping review of early interventions for parents of deaf infants

The World Health Organisation (WHO) reports that around 34 million children worldwide are deaf (>40 decibels hearing loss (dBHL) in the better hearing ear) [1]. The Consortium for Research into Deaf Education (CRIDE) survey estimated that there are at least 53,954 deaf (all levels of deafness, from mild to profound) children from birth up to the age of 19 years 11 months in the UK [2]. Over 90% of deaf children in the UK are born to hearing parents, most of whom were not expecting a deaf child [3, 4] and whom may require specialist support and advice.

There is a body of evidence that a significant number of deaf children experience poorer outcomes than hearing children, in terms of educational attainment [5], social domains [6] as well as poorer long term outcomes including increased unemployment [7]. Being deaf can have a range of impacts for both the child and their family [8] including auditory, linguistic, cognitive, social, literacy, and academic functioning [9]. Early language deprivation and language delay can lead to challenges in many developmental domains [10‐16] including communication challenges [17, 18], poorer written language [19] and poor academic outcomes [20]. Additionally some deaf children can display difficulties in executive functioning [21], abstract thinking and problem-solving skills that adversely affect academic achievement [22].

Language delay [23‐25] thought to be associated with language deprivation [26, 27] can in turn lead to delays in Theory of Mind (ToM) (empathy-related) skills [14]. For example, research has shown deaf toddlers exchanging fewer social-communicative signals and having more difficulties understanding the intentions of others [28]. Social and emotional development provides the foundation for how people feel about themselves and experience interactions with others and begins at birth, continuing throughout the lifespan [29]. This unique pattern of social and emotional development may predispose to both serious social challenges and increased psychological distress [15, 30] and are related to a range of other poor socio-emotional outcomes [17, 20, 31].

Problems initiating and sustaining peer relationships and development of self-esteem [32] compound challenges in social settings. Social isolation and low popularity status during childhood have been shown to predict poor emotional well-being in the short term and future adverse consequences for mental health [14, 33]. Deaf children across England not in contact with mental health services have been found to have 2 to 3 times the rates of mental health problems compared to other children [34] and a systematic review found higher rates of behaviour problems in deaf children across numerous countries [35].

The Universal Newborn Hearing Screening Programme (UNHSP) was introduced across the UK between 2002 and 2006 [36] to screen all infants shortly after birth for signs that they may be deaf. Results to date suggest positive associated language [37] and health economic [38] outcomes. Early detection followed by specialist support programmes have been found to improve many negative outcomes for deaf children [39‐41] including language acquisition and learning skills [29, 42, 43]. However, the outcomes for deaf children are highly variable due to many different factors including those described above [44].

On learning that their child is deaf, parents require a level of emotional support to adjust to this new information during the transition from diagnosis to early management [45, 46]. Families must navigate through a myriad of services and choices including the NHS, local authorities and private agencies, and their own family constructs, all of which requires sensitivity to the social and emotional needs of a family with a deaf baby [47]. A consensus statement on early intervention lays out aspirations for good practice [48]. Current guidance is that early intervention for deaf infants should include parents as the most important agents for supporting their young children’s language development [16] and that professionals who work with parents should focus on promoting their abilities to provide a language-rich environment [42, 48, 49]. Family-centred care has been advocated as the optimal way of addressing family needs in early intervention [50].

Most countries provide a range of support to families during early hearing detection and intervention programs. In the US parents receive information from an audiologist, written information and discussion with a medical professional [50]. Various states offer different additional support. For example in Colorado, USA all families of diagnosed children are referred to an early intervention system that begins with a counselling and information session with a deaf early intervention provider. Subsequently an early intervention co-ordinator consults with the family, establishes links to the local education pathways, offers access to sign language training for the family and engages them in a 6 month state wide program of support. This is offered to all families. However there has been no randomised controlled trial (RCT) to evaluate this to date, and no other published studies which met our PICOS criteria and so it does not appear in this review. In the UK Qualified Teachers of the Deaf (QToD) play an important role in providing early education services to families of infants and toddlers with hearing loss [51]. There is an element of universal provision but these services are often needs led depending on factors including audiological evaluation, child factors such as other significant medical conditions, social factors and parental choice. Current protocol in England is that every child identified by the UNHSP is contacted by a QToD within two working days post-referral [52]. The QToD works closely with the parent after the initial meeting and diagnostic period. This support is ongoing during the pre-school period. Formal parent support interventions are not often used but the regular QToD support is holistic, not just concentrating on language and communication but also on social and emotional development, audiological support and signposting to additional services if necessary. Many services will use the National Sensory Impairment Partnership (NatSIP) Eligibility Framework [53] and their specific early years’ guidelines [54, 55] to determine levels of support according to individual need. This framework includes weighting of specific criteria but it is clear there still needs to be a focus on individual needs. However, provision is not universal, leading to variable offers for parents in different localities which may lead to deaf babies and young children of similar need getting inconsistent support due to a lack of resources despite the best efforts of specialist services. One study in Australia has reported such a challenge with many gaps in family-centred service provision at the time of identification and after enrolment in early hearing intervention services [18].

Many UK services have an Early Years (EYs) specialist QToD who works with these families at this stage. They may follow the Early Support Monitoring Protocol (revised from September 2020 as Success from the Start) but this is not mandatory, nor is it a formal intervention programme but a developmental resource used mainly to work with families to support them to observe, monitor and record progress their children make. QToDs receive some early years guidance during their training, delivered within the full training protocol.

Even where intervention is available, families are extremely diverse and several factors may hinder families from accessing early intervention. These include language barriers with parents, lack of availability as well as cultural challenges during audiological testing (e.g., families sometimes preferred male practitioners, cultures where disability is stigmatised sometimes leading to caregivers denying the hearing loss or declining support or amplification for their children) [56].

Based on an ever-growing body of research, family-centred practices are a recommended, evidence-based principle of early childhood intervention but there continues to be a gap between recommendations and implementation of such practice across all disciplines [57].

A comprehensive synthesis of the available research evidence is necessary to inform a discussion about appropriate provision of support and interventions for parents of deaf infants. A well-established key criterion for the implementation of screening in society is the existence of a helpful and accepted intervention [58] which in the context of new-born hearing screening is early intervention with parents [48, 59].

Prior to running literature searches the study team held national workshops with service providers and academics to gather information about the support that services currently offer parents of deaf infants aged 0-5 years old. The workshops included presentations and group discussions about good practice, the eligibility criteria for access to interventions, barriers to practice and gaps in research. The research team also held a meeting with parents of deaf infants to gather information about their experiences of the support they have been offered. Notes from discussion at these workshops and meetings were collated and key intervention elements and outcomes were identified, and included in the comprehensive search strategy for the systematic scoping review.

Key stakeholders were identified from the workshops and invited to form an expert panel. The search strategy and PICOS criteria were developed with input from the workshops and finalised with the expert panel.

The final PICOS were as follows:

A search strategy was designed to capture the population of parents/caregivers of children diagnosed as deaf and a range of interventions (based on existing knowledge and feedback from the stakeholder workshops). A full search strategy can be found in Additional file 1.

Searches were loaded into EndNote bibliographic software and then transferred to an Excel database for sifting. The searches were run by an information specialist at the Centre for Reviews and Dissemination (CRD, University of York) on the following databases in September 2019: CINAHL, Cochrane Central Register of Controlled Trials (CENTRAL), Embase, MEDLINE, PsycINFO, Science Citation Index, Scopus and Social Science Citation Index.

Two independent reviewers conducted screening over three sifting stages. References of reviews, books, and included literature were checked to ensure all relevant papers were identified. Agreement for each sift was calculated over a minimum 10% overlap, and was consistently above the pre-specified 80%. Disagreements were discussed and resolved with a third independent reviewer. Authors were contacted where necessary to clarify outcome measures and results.

For each eligible study, data was extracted by two reviewers using the Template for Intervention Description and Replication (TIDieR) checklist [60] as a guideline for descriptions of included interventions. The two reviewers conducted quality assessment using the Revised Cochrane Collaborations Assessment Tool for Assessing Risk of Bias in Randomised Trials (ROB-2) [61] tool for RCTs and the Risk Of Bias In Non-Randomised Studies of Interventions tool (ROBINS-I) [62] for non-randomised studies (comparison groups and pre-post study designs). Additional file 2 includes a table (Table 1) of characteristics for included studies in the review. This presents further detail on the data extracted.

For randomised controlled trial studies only, we compared these to the elements outlined in the International Consensus Statement [48] to determine how many of these 10 principles of best practise were included.

The final included studies were discussed at an expert panel meeting. At this meeting we discussed the most appropriate way to present the studies as well as the key outcomes to share. As a result, themes were identified, based on the primary focus of the intervention, and these have been used to summarise the studies.

The following interventions were found to have a significant effect in randomised controlled trials:

There is currently a ‘Best Practices in Family-Centered Early Intervention for Children Who Are Deaf or Hard of Hearing: An International Consensus Statement’ [48] of 10 principles which are deemed to be best practice for early intervention in this population. We mapped the interventions with RCT evidence to these 10 principles: however we found that none of the 5 RCTs included all 10 of the consensus principles. Commonly included was Principle 4: Family Social and Emotional Support, whereby families were provided with support systems to help them access knowledge and experience, and Principle 7: Qualified Providers, where those providing services to families had the necessary knowledge and experience. The included RCTs were less likely to report on Principle 3: Informed choice and decision making, relating to interventions where services provide families with the knowledge to make decisions based on special education laws and their rights and Principle 9: Progress Monitoring, relating to regular assessments of progress throughout the intervention. However, when comparing to the 10 consensus principles, we were only able to use available information about the intervention as provided in the papers, which were often limited in detail.

There were 9 studies focused on language and communication, 6 of which found a significant effect. These included studies which aimed to teach caregivers strategies to improve use of sign language and child vocabulary such as Adult "recasting" in sign language [68] and the ASPIRE Intervention Curriculum [69]. Auditory Verbal (AV) therapy [70] was also found to significantly improve language development in children using hearing technologies, and the Tri sensory language stimulation [71] found significant effects on nine out of nineteen variables related to language and vocabulary learning. Other studies included comprehensive training programmes, such as Bill Wilkerson Hearing and Speech Centre Program [72]. They found that children receiving early intervention had similar language competence to that of hearing children, and performed significantly better than those receiving late intervention. The Counselling and Home Training Program for Deaf Children [73] is a family oriented programme that encourages natural communication and building competence and esteem in a secure family context. The 1984 publication focuses on communication outcomes, with significantly more developmentally mature communication and high interaction in families who had received the intervention.

There were 3 studies which showed non-significant improvements from the intervention on the child’s language and communication; these include the Tracy Clinic Oral Preschool [74]; a Parent Orientation Program [75] which focuses on early exposure to manual communication and The SKI*HI program [76] which teaches parents how to provide auditory and language stimulation for the child in the home.

4 studies focused on parental knowledge and skills, with significant results for a second study of PCIT [77] where reported outcomes focused on parent skills and managing child behaviour. There were also significant results for Interactive Storybook Reading [78], where the main outcomes focused on parent behavior, engagement, teacher techniques, and interactive reading. 2 studies showed non-significant improvements; the Deaf Mentorship Programme [79] where deaf adult mentors visit families to share their language, culture, and personal knowledge and the Parent Study Group [80] which is based on the Adlerian Model and helps parents manage their child’s behaviour.

Both of the studies focused on parent wellbeing and empowerment showed significant results. These include The Counselling and Home Training Program for Deaf Children [81] which reports reduced parenting stress, and the family focused early intervention group [82] which focuses on home training for families in rural areas.

Both of the studies that focused on parent child relationships showed non-significant improvements in parental scores on the Emotional Availability Scales: Psychosocial video intervention, [83] and on the Gerrard parent-child questionnaire: Faranak parent-child program, [84].

7 studies focused on language and communication, four of which showed significant results for increases in parent facilitation of spoken language: Parental Training Course, [85]; parent conversational ability Hanen based training program, [86]; child vocalisations ASPIRE intervention, [87]; and child hearing and speech skills Parent counselling, [88]. The other three studies showed non-significant improvements in learning and expression of language: Total communication, [89] and gains in child vocabulary SSE-2, [90]; Parent and child training, [91].

Of the 3 studies focused on parent wellbeing and empowerment, a group counselling programme showed significant improvements for parents: Parent Group Counselling Programme [92]. A remote intervention delivery service found no difference between tele intervention and conventional intervention in terms of communication performance of children meaning that telecommunication could be used as effectively as face to face; Tele intervention [93]. There were non-significant improvements for families in the HI HOPES [94] intervention, which has the central aim of informing and equipping parents to make their own decisions and measured parent satisfaction and child language outcomes.

The remaining 2 pre/post study designs focused on parental knowledge and skills, with a storybook reading programme reporting non-significant improvements: Parent child reading training [95] and on the parent child relationship, with a video feedback intervention showing non-significant maintenance and improvement on parent Emotional Availability scores: Video Interaction Guidance (VIG) [96].

For those studies that used other study designs, 11 focused on language and communication. Hogan et al. [97] predicted language scores based off modelling for Auditory-Verbal Therapy, but found no significant difference in rate of language development. Calderon and Low [98] conducted a sub-analysis of a larger study of Early Childhood Home Instruction and found non-significant improvements in language when a father was present at the intervention. Three studies looked at language communication using a longitudinal design; Oral Language Training [99]; Central Institute for the Deaf Early Education Project [100]; A Good Future for Deaf Children Programme [101], and all found improvements in language and communication for the child. There were also 6 papers that reported results from either case or file review, or case studies, all reporting improvements for the child’s language; Auditory-Verbal Therapy [102]; The 10-year-old Early Childhood Home Instruction Program for Hearing-Impaired Infants and Their Families [103]; PiCS Intervention using distance education technology [104]; A program for teaching written language [105]; HI CHIPS Total Communication Program [106]; Communication Program [107].

8 studies focused on parental knowledge and skills including one logic model evaluation testing The Shared Reading Project [108]. There were 5 case studies, 3 showing positive changes for families; Parent Hearing Aid check training [109]; Educator-oriented contact intervention program [110]; Treatment Program [111]; one showing highly mixed results; Iowa E-Book [112], and one showing the intervention to be not effective at changing parent behaviour: Parent Training on Storybook Reading [113].

One study focused on parent wellbeing and empowerment using a retrospective survey design; Diagnostic Early Intervention Program (DEIP) [114], with findings showing family involvement and early enrolment as important factors for improving child outcomes.

The remaining 2 studies based on parental knowledge and skills were qualitative; Family-oriented early intervention program [115]; ASL Parent-Child Mother Goose [116], with both finding positive impacts for mothers.