Does early cochlear implantation promote better reading comprehension skills?

Abstract

Objective: to investigate the effect of age at CI activation and to explore the role of other variables such as linguistic skills, stimulation modality and gender on reading comprehension.

Study design: Prospective observational nonrandomized study.

Methods: 89 children with profound congenital sensorineural hearing loss were included in the study. The mean age at CI activation was 21 months (DS ± 11; range 7-50). The Italian reading standardized test, "Prove di lettura MT", was used to assess reading comprehension. The individual raw data MT score were converted into z scores (expected values: means = 0 and SD = 1). The positive values indicated better performance and negative values indicated worse performance.

Results: Early implanted children achieved significantly better reading comprehension skills, 55 out of 89 children are within 1 SD from the overall mean. 34 children (38.2%) attainted MT z-scores less than 1 SD below the mean. Children with unilateral CI performed somewhat worse if compared to bilateral CI and bimodal stimulation mode, although the differences were weakly significant from a statistical point of view. A strong and positive correlation (rho .69, p < .001) was found with the lexical and morphosyntactic comprehension (rho .70, p < .001). Not significantly different values were observed for gender and parental education level.

Conclusion: Early cochlear implantation promoted better development of reading skills in children with cochlear implantation. LEVEL OF EVIDENCES: outcomes research.

Keywords: Cochlear implant; Linguistic ability; Reading comprehension.