Document Type

Capstone Project

Publication Date

Spring 5-11-2017



Hearing screenings for the pediatric population are intended to identify hearing losses that may otherwise go undetected. Otoacoustic Emissions (OAEs) are a screening tool that is quick, easy to administer, and requires little to no participation from the participant. A recent study in our lab has examined the impact of probe type and digital noise reduction on signal amplitude, noise floor amplitude, and test-retest reliability for Distortion Product Otoacoustic Emission (DPOAE) testing in young normal hearing adults. Signal-to-noise ratios were similar between the two devices. However, response amplitude, noise floor and test retest reliability were significantly different between devices. The device with a foam ear tip had greater response amplitude and better test-retest reliability compared to the device with a rubber probe tip. The device with the rubber-tip likely had similar SNRs due to digital noise reduction. The aim of the current study is to compare these results from young normal hearing adults with results from pre-school aged children. DPOAEs were measured twice in both ears under two conditions. One condition with the Natus AuDx (using foam probe tips without digital noise reduction) and one condition with the Etymotic (Maico) Eroscan Pro OAE screener (using rubber tips with digital noise reduction). Data from preschoolers does not support the findings for adults. DP amplitudes were greater across all frequencies with EROSCAN and test retest differences were high for both devices compared to the study with adults. Also, SNRs were better for preschoolers with EROSCAN, likely a result of greater response amplitude compared to AuDx. This likely relates to the smaller ear canal volume in preschools compared to adults, and the possibility of deeper probe-tip insertion with EROSCAN.