Systematic review
Communication modes for children with cochlear implant
Systematic review
|Updated
The objective of this systematic review was to summarize recent studies comparing the effect of using spoken language and sign language, spoken language with sign support or spoken language alone.
Key message
Approximately 90 to 95 % of deaf children in Norway are offered a cochlear implant (CI) in one or both ears. CI is an advanced hearing aid aimed to recognize sounds. Parents of children with CI have to choose preferred communication mode for their child. In Norway there are mainly three approaches: use of both spoken language and sign language (bilingual communication), spoken language with sign support and spoken language alone (oral communication).
The objective of this systematic review was to summarize recent studies comparing the effect of using spoken language and sign language, spoken language with sign support or spoken language alone. We have also looked at studies on total communication, a communication mode used in the U.S., consisting of different elements of spoken language, sign support or sign language. We included studies where children had CI implanted before the age of three and we tried to answer the following question: How does the chosen communication mode affect the children's sound and speech recognition, their speech and language perception and production, their quality of life, social participation and any other outcome?
It is uncertain what effect using spoken language and sign language, spoken language with sign support or spoken language alone have on children who have been implanted with CI by the age of three. The quality of the documentation is very low. We found four studies that compared total communication with spoken language alone. The quality of the documentation was very low and the results had limited external validity. We found no studies on children who used both spoken language and sign language and no studies that measured the children’s quality of life or social participation.
Summary
Background
Every year approximately 40 deaf children are born in Norway. Approximately 90 to 95 % of deaf children in Norway are offered a cochlear implant (CI) in one or both ears. CI is an advanced hearing aid that helps children to perceive sound. Children with CI have special follow-up needs and their parents have to decide preferred communication mode for their child. In Norway, there are mainly three approaches: use of both spoken language and sign language (bilingual communication), spoken language with sign support or spoken language alone (oral communication).
Objective
The objective of this systematic review was to summarize recent studies that evaluate the effect of using spoken language and sign language, spoken language with sign support or spoken language alone. We have also included studies on total communication, a communication mode used in the U.S., consisting of different elements of speech, sign support or sign language. We included studies on children who had been implanted with CI by the age of three and we tried to answer the following question: What effect does the chosen communication mode have on the children's sound and speech recognition, their speech and language perception and production, their quality of life, social participation and any other outcome?
Method
We performed a systematic literature search in MEDLINE, EMBASE, PsycINFO, British Nursing Index, ERIC, Social Science/Science Citation Index, SveMed+, AMED, SpeechBite, NARIC, OpenSIGLE og WHO Clinical Trials Registry, Cochrane CENTRAL, Cochrane Database of Systematic Reviews, Health Technology Assessments (HTA) and Database of Abstracts of Reviews of Effects (DARE). The literature search was limited to publications published as of 2000. We also reviewed reference lists received from the reference group.
Inclusion criteria for study design were systematic reviews, randomised controlled trials, controlled before- and after studies, case control studies, cohort studies and cross-sectional studies with control groups. Patient series were included and cited.
The publications that met the inclusion criteria were obtained in full text and critically appraised for methodological quality by two people. The quality of the documentation, which shows the degree of confidence we have in the results, was assessed with GRADE (Grades of Recommendation, Assessment, Development and Evaluation).
Results
The literature search identified 1514 unique references, and we read three reference lists received from the reference group. 91 of the publications were reviewed in full text. Of these, six American cohort studies of moderate methodological quality met the inclusion criteria. We also found three relevant patient series and 17 cross-sectional studies with control groups.
We did not find any studies examining the effects of using both spoken language and sign language. The six cohort studies compared children who used spoken language alone with children who used total communication. The studies reported the children's sound and speech recognition, their language perception, language production and speech production. None of the studies reported the children's quality of life and social participation.
Four of the cohort studies evaluated the effect of the communication modes. Some found statistically significant differences in favour of oral communication (measured on sound and speech recognition, language reception and production), but the children using oral communication started with better scores before implantation, and the development curves appeared to be similar in both groups. One study reported that the children who used total communication had significant better language production compared to the children who used spoken language alone, but the author of the study comments that this may be due to other factors than the used communication mode. The quality of the evidence, assessed with GRADE, was very low. This means that we cannot conclude about the effectiveness of the used communication modes. Many of the studies found that the children in both groups showed significant improvements on all reported outcomes.
Discussion
It is hard to say whether the reported outcomes are related to the chosen communication mode or other factors. The quality of the evidence was very low. Hence all results related to the relative effectiveness of communication modes are highly uncertain. They were based on a small number of studies which had a high risk of systematic errors related to group allocation and measurement methods. The studies lacked descriptions of details related to the children's education, and they had low external validity. We found no studies on children using bilingual communication (spoken language and sign language). The results from the cohort studies without effect estimates, the cross sectional studies and the patient series were not included in the conclusion about the effects of communication modes.
Conclusion
The included studies did not provide enough evidence to conclude how the use of total communication or spoken language alone (oral communication) affects children’s speech- or language development. We did not identify any studies on children who used spoken language and sign language (bilingual communication). Nor did we find studies that measured the children's quality of life or their social participation. The quality of the documentation was very low, and the results may have limited external validity.
On the basis of the identified studies we have no scientific evidence of the relative effectiveness of the different communication modes. There is a need for methodologically well-designed observational studies which study the development in children with CI over time, and which include information about the children’s linguistic, educational and social context.