Is behavioral audiometry achievable in infants younger than 6 months of age?

Abstract

Background and goal: When carried out in addition to objective tests, behavioral audiometry performed in children with the so-called "Delaroche protocol" [IJORL 68 (2004) 1233-1243] enables to determine hearing thresholds by air and bone conduction over the whole auditory frequency range. In the present report, seventy-three hearing-impaired infants with different levels of motor and cognitive development were tested behaviorally before 6 months of age. Reliability of these early determined behavioral thresholds was then after analyzed using: (a) cross-sectional study, and (b) longitudinal study.

Methods: Cross-sectional study compared click-evoked ABR thresholds in the better ear with binaural high-frequency hearing thresholds. In longitudinal study, early measured binaural hearing thresholds from 500 through 4000 Hz were reassessed at 18 months.

Results: In 13% of babies behavioral testing was not fully completed by 6 months of age. Nevertheless, both cross-sectional and longitudinal studies yielded intraclass correlation coefficients above 0.80, suggesting that behavioral testing is applicable to this very young population.

Conclusions: Assessment of hearing after newborn screening should not be restricted to objective tests before 5 ½ months. It should also include bone- and air-conduction behavioral tests adjusted to developmental stage and performed in presence of parents.