Cochlear implantation outcome for deaf children with additional disabilities: a systematic review

Objective: To investigate the improvement in different skills following cochlear implantation (CI) in deaf children with additional disabilities (AD), and present an overview of the different outcome measures and the corresponding tests used. Methods: The MEDLINE and Embase databases were searched for studies published in English, Italian, French, German, Spanish or Dutch, up to 4 December 2013, including studies published ahead of print. The search was directed toward studies with a clear diagnosis of additional disability. Only studies including a comparison with pre-CI data of the same group or with post-CI performance of a control group were retained. Two reviewers independently assessed methodological quality and extracted data from the studies by means of forms. Because of the heterogeneity of the study groups and the reported outcome measures, meta-analysis was not possible. Data were collected in tables and described by means of a structured review. Results: The initial search yielded 464 unique studies, of which 41 met the inclusion criteria. These studies show that children with AD improve on average in most of the outcome measures, although often to a lesser degree and more slowly than their peers with cochlear implants and no AD. However, in cases of mild AD, they may reach similar skills to normally developing peers. Many receive measurable benefit from CI that adds to their quality of life. Conclusions: There is a need for alternative tools for measuring those outcomes that are difficult to quantify. Early implantation appears to be beneficial and, over the last 13 years, the mean average age of CI in children with AD decreased from 45 to 30 months. There is ample consensus that cognitive and global developmental levels have significant implications for expectation of benefit and are accurate predictors of certain outcomes