A Systematic Review of the Literature on Early Intervention for Children With a Permanent Hearing Loss
Kumar, S., Jeffries, L., et al. (2008).
Brisbane (Australia): Centre for Allied Health Evidence.
This systematic review investigates the effects of individual characteristics and early intervention factors (e.g., age of hearing loss detection, severity of hearing loss, social and cultural factors, access to hearing devices, access to oral or signed communication, amount of intervention) on communication, learning, and participation outcomes in infants and young children identified with permanent bilateral hearing loss prior to 36 months of age.
Queensland Government (Australia)
1995 to November 2006
All original empirical research, including quantitative and qualitative research designs
168
"In younger children (5;0 years and under), parental involvement was found to contribute to positive findings in terms of receptive vocabulary, language skills, cognitive ability, and functioning and reading ability. However no such findings could be extrapolated for socio-emotional development" (p. 319). Due to the limited number of studies available, results should be interpreted with caution and additional research is required.
"There is literature evidence to suggest that children who use hearing technology (such as a hearing aid or cochlear implant) and are exposed to oral communication programs have positive outcomes for speech perception and production" (p. 493). However, given the nature of these findings, generalization is discouraged.
A limited evidence base of four heterogeneous studies found that using oral language and signing together seem to improve access to vocabulary and grammar than either modality alone for children with hearing loss. Signing improved a child’s ability to access meaning no matter which modality was dominant. Further research is needed to draw conclusions.
"Whilst high level evidence is lacking (Level I and II), there is a sufficient number of methodologically strong research publications (Level III) that support the use of early detection and early intervention for children who have a hearing loss. This body of evidence indicates that the earlier the detection and subsequent intervention, the better the outcomes are for children who have a hearing loss" (p. 492).
<p>The evidence base for cochlear implantation (CI) in children with hearing loss indicates:</p>
<ul>
<li>CI may improve speech and language outcomes, though more research is needed.</li>
<li>"The younger a child is when they receive a cochlear implant, the better the outcomes. However, there is no consensus regarding a minimum age or an optimum age for implantation" (p. 204).</li>
<li>Research is limited to children receiving an implant at 1;0 year or older.</li>
<li>Longer duration of CI use is associated with positive outcomes in speech perception and production.</li>
</ul>
"The literature also highlights the need for services which are centred toward the child and the family of the child who has a hearing loss" (p. 493). Limited evidence indicates that no one characteristic of service delivery results in improved outcomes and that many interrelated factors influence outcomes.
<p>In regards to hearing aid use in children with hearing loss:</p>
<ul>
<li>Two studies found that longer duration of hearing aid use results in improved receptive and expressive vocabulary; and</li>
<li>One study showed differences in unilateral versus bilateral hearing aid use.</li>
</ul>
Overall, the literature indicates that there is no single communication modality (e.g., auditory-oral, sign language, total communication) ideal for all children with hearing loss. Additionally, the best mode of communication may change at different stages of a child’s development.
"There is increasing evidence to suggest that the earlier a child [with hearing loss] has access to hearing technology the better their outcomes are likely to be. To date, the emerging evidence clearly highlights the importance of early access to these technologies and their positive influence on outcomes" (p. 493).
"There is little high level, high quality evidence that explicitly investigates service or program constructs and their overall impact on outcomes for children who have a hearing loss. In general, existing literature evidence indicates that program characteristics (such as hours per week of intervention, therapist experience) and educational placements (such as public versus private, and home versus centre-based) in isolation, have minimal impact on outcomes. However, given the limited amount of literature evidence, there is a need for ongoing evaluation and monitoring of the impact of these variables on outcomes for children who have a hearing loss" (p. 493).
