Assessing consonant production in children with cochlear implants

Objective: The objective of this study was to investigate the development of consonant inventory and accuracy in pediatric cochlear implant (CI) recipients and compare their performance to typical hearing (TH) children. Methods: One hundred and twenty nine children with CIs, implanted between 6-38 months of age, and 30 age-matched children with TH participated in this study. Spontaneous speech samples were collected at 3.5 and 4.5 years chronological age and the first 100 different words spoken by each participant were transcribed. Two consonant production measures were subsequently calculated to assess consonant acquisition and mastery. The percentage of Consonants Correct (CC) was used for measuring accuracy and Consonant Diversity (CD), an inventory measure, was used to identify the number of different consonants spoken by each participant. Repeated measures analyses of variance were conducted to examine the differences in consonant production scores based on presence of CI (participants with CI versus typical hearing (TH) participants), and chronological age at data collection (3.5 years versus 4.5 years). Results: CI recipients displayed lower consonant production scores compared to TH children. Children with the most device experience (32-38 months at 3.5 years) performed on par with their TH peers. Conclusions: The two measures used in this study together appear capable of comprehensively describing the changes in consonant production skills of children. Results from this study indicate that while most CI participants display lower scores compared to TH children, many of the CI users are able to produce speech sounds on par with TH children.