Relationships between otoacoustic emissions and auditory brainstem responses in neonates and young children: a correlation and factor analytical study.

Abstract

To establish relationships among transient evoked otoacoustic emission (TEOAE) and auditory brainstem response (ABR) variables in a sample of normal hearing neonates and young children, ranging in age from approximately 3 weeks to 4 years. Retrospective, non-randomized, cross-sectional analysis of clinical data obtained at a tertiary care medical center. Pearson product moment and Spearman rank order correlation analyses to evaluate pairwise relationships between TEOAE variables, ABR variables and age; factor analysis, to identify the structural composition and dimensionality of these relationships. Significant pairwise correlations were obtained between variables within each test paradigm (TEOAEs, ABRs) and between ABR absolute and interpeak latencies with age. However, the most striking effect was the absence of strong correlations between ABR and TEOAE variables, indicating that these test measures provide independent information about auditory system integrity and sensitivity. Two factors, accounting for over 55% of the variance, characterized this data set: 1) a frequency-dependent OAE factor, which showed an inverse relation between biologic noise and whole wave percent reproducibility and half-octave band TEOAE amplitudes; and 2) a central nervous system (CNS) maturational factor, which showed an inverse relationship between age and certain absolute and interpeak ABR latency components. TEOAE and ABR test results provide unique and functionally independent information about normal auditory system integrity and sensitivity. Therefore, a combination of both tests is well suited for use within a pediatric test battery. These results confirm that biologic noise and age at test differentially affect OAE and ABR test measures, and both effects require consideration during data acquisition and interpretation.