Do Adolescent Hearing Aid Users Prefer Digital Noise Reduction to Be Activated? Findings From the Laboratory and Home...

The purpose of this study was to evaluate the effects of an advanced digital noise reduction algorithm on measures in the laboratory (double-blind paired comparison testing, unblinded slider setting, sentence recognition performance) and during a field trial (unblinded slider setting). A secondary purpose was to evaluate participants' ability and willingness to use a smartphone application for controlling the algorithm in the field.

Laboratory procedures included the evaluation of subjective ratings of listening ease using a double-blinded, paired comparisons approach while listening to speech in background noise. Participants were trained to use a smartphone application for manually controlling the advanced digital noise reduction algorithm and they indicated their preferred setting using the smartphone application, also in the laboratory. In addition, they completed double-blinded, behavioral sentence recognition in noise testing with a variety of advanced noise reduction settings. Finally, participants wore the hearing aids at home during a field trial, with instructions to use the smartphone application during the trial in noisy situations and to report on their experiences using a bespoke questionnaire upon their return to the laboratory.

Double-blind, paired comparison testing revealed that most participants (80%) preferred to have advanced digital noise reduction active in the noisy, reverberant laboratory. These participants were also likely to demonstrate a preference for the advanced digital noise reduction to be active during the unblinded preference task. Advanced digital noise reduction did not affect sentence recognition in noise performance. During the field trial, participants could use the smartphone application to adjust the advanced noise reduction strength in noisy situations but did not choose to do so frequently. In addition, on average, participants did not activate the advanced digital noise reduction algorithm when in self-identified difficult listening situations during the field trial.

The results of the current study demonstrate robust subjective benefits of advanced digital noise activation in the laboratory, with no effects on speech intelligibility. In addition, participants were internally consistent in the laboratory; their self-adjusted settings were consistent with the program they preferred during the double-blind, paired comparisons testing. However, the findings with the smartphone application demonstrate that, in general, they did not activate the advanced digital noise reduction during their self-identified difficult listening situations in the field. This result could partially be explained by the limited reported use of the smartphone application during the field trial. Future study is warranted to reconcile the laboratory and field trial findings in this study. In the interim, a reasonable clinical approach with limited negative speech intelligibility consequences might be to activate advanced digital noise reduction by default and provide smartphone application access in case a patient discovers a preference for an alternative noise reduction strength.