8Paediatric Outcomes: Language, Literacy and School
For a deaf child, the implant is judged not by a word score but by whether spoken language, reading and a mainstream classroom become realistic. The CDaCI study followed implanted children prospectively and showed that the device reliably bends the language-growth trajectory upward, that age at implantation matters, and that the earliest-implanted children can track close to hearing peers. A residual gap often persists, most visibly in reading and writing, but the population-level shift since the pre-implant era is large.
CThe CDaCI evidence base
The Childhood Development after Cochlear Implantation study prospectively followed 188 children implanted before age 5 across six US centres against 97 normal-hearing children over three years. Implantation produced consistent gains in the rate of spoken-language growth, so children narrowed rather than widened the gap with hearing peers over time. Age at implantation was a significant independent predictor of the level of spoken language ultimately achieved. A prospective design with a hearing comparison group gave these conclusions weight that earlier single-centre retrospective series lacked.[2010]
CAge at implantation and the sensitive period
Children implanted before about 18 months kept comprehension and expressive-language scores roughly within one standard deviation of normal-hearing peers; later-implanted children showed progressively larger gaps. Pooled multicentre data found that around 81% of children implanted before 12 months reached normal vocabulary development. Late first-language exposure is followed by a roughly linear decline in eventual language competence, whether the language is spoken or signed, consistent with a sensitive period. The argument for early implantation is therefore developmental, not merely audiological: the cortex is most receptive to organising language input in the first years of life.[2010][2016][2009]
CLiteracy and reading
Among adolescents with long implant experience, roughly 47 to 66% scored within or above the average range for hearing age-mates on standardised reading tests, depending on the measure. About 36% read at ninth-grade level or above, a marked improvement over the pre-implant era when most profoundly deaf school-leavers read far below grade level. Writing and spelling lagged behind reading, and phonological-processing tasks remained relatively hard, exposing where the residual gap concentrates. Around 72% of these adolescents held their reading standing relative to hearing peers across years of schooling, indicating age-appropriate growth rather than a widening gap.[2011][2009]
CEducational placement and the residual gap
Better reading achievement was associated with mainstream educational placement, updated implant technology and stronger cognitive-processing skills such as longer memory spans. Higher nonverbal intelligence and family socioeconomic status also tracked with stronger literacy, underlining that outcome is multifactorial. Mainstream placement has become a realistic and common goal for early-implanted children, a shift from the special-school default of the pre-implant era. A residual gap with hearing peers, concentrated in writing, spelling and complex language, often persists and should be set as a realistic expectation rather than treated as failure.[2011][2010]
Based on CDaCI-era evidence, what is the most accurate counselling?
In the CDaCI study, children implanted before approximately which age tended to keep language scores within about one standard deviation of normal-hearing peers?
Which factor was associated with better reading achievement in adolescents with cochlear implants?