Auditory development in early amplified children: factors influencing auditory-based communication outcomes in children with hearing loss.
OBJECTIVE
The purpose of this study was to determine the influence of selected predictive factors, primarily age at fitting of amplification and degree of hearing loss, on auditory-based outcomes in young children with bilateral sensorineural hearing loss.


METHODS
Forty-four infants and toddlers, first identified with mild to profound bilateral hearing loss, who were being fitted with amplification were enrolled in the study and followed longitudinally. Subjects were otherwise typically developing with no evidence of cognitive, motor, or visual impairment. A variety of subject factors were measured or documented and used as predictor variables, including age at fitting of amplification, degree of hearing loss in the better hearing ear, cochlear implant status, intensity of oral education, parent-child interaction, and the number of languages spoken in the home. These factors were used in a linear multiple regression analysis to assess their contribution to auditory-based communication outcomes. Five outcome measures, evaluated at regular intervals in children starting at age 3, included measures of speech perception (Pediatric Speech Intelligibility and Online Imitative Test of Speech Pattern Contrast Perception), speech production (Arizona-3), and spoken language (Reynell Expressive and Receptive Language).


RESULTS
The age at fitting of amplification ranged from 1 to 72 mo, and the degree of hearing loss ranged from mild to profound. Age at fitting of amplification showed the largest influence and was a significant factor in all outcome models. The degree of hearing loss was an important factor in the modeling of speech production and spoken language outcomes. Cochlear implant use was the other factor that contributed significantly to speech perception, speech production, and language outcomes. Other factors contributed sparsely to the models.


CONCLUSIONS
Prospective longitudinal studies of children are important to establish relationships between subject factors and outcomes. This study clearly demonstrated the importance of early amplification on communication outcomes. This demonstration required a participant pool that included children who have been fit at very early ages and who represent all degrees of hearing loss. Limitations of longitudinal studies include selection biases. Families who enroll tend to have high levels of education and rate highly on cooperation and compliance measures. Although valuable information can be extracted from prospective studies, not all factors can be evaluated because of enrollment constraints.
Sininger
Yvonne S
YS
Division of Head and Neck Surgery, David Geffen School of Medicine at UCLA, Los Angeles, California, USA. ysininger@mednet.ucla.edu
Grimes
Alison
A
Christensen
Elizabeth
E
D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D003054:Cochlear Implants; D003071:Cognition; D006310:Hearing Aids; D006312:Hearing Loss, Bilateral / Q000628:therapy*; D006319:Hearing Loss, Sensorineural / Q000628:therapy; D006801:Humans; D007223:Infant; D007361:Intelligence Tests; D007804:Language Development; D007805:Language Development Disorders / Q000517:prevention & control*; D009048:Motor Skills; D019303:Multilingualism; D010287:Parent-Child Relations; D011237:Predictive Value of Tests; D012720:Severity of Illness Index; D013060:Speech; D013064:Speech Disorders / Q000517:prevention & control*; D013065:Speech Intelligibility; D013067:Speech Perception; D016896:Treatment Outcome