The Effect of a Third In-Ear Microphone on User Satisfaction, Speech Intelligibility, and the Real-Ear Gain of Hearing Aids at a Conversational Level in Patients with Moderate Hearing Loss

<b>Background:</b> The microphone & receiver-in-ear (M&RIE) integrates two traditional hearing aid microphones, while an additional in-ear microphone helps preserve natural sound perception. However, the impact of this third microphone on hearing aid amplification remains unclear in patients with moderate hearing loss. <b>Methods:</b> In this prospective crossover study, thirty-nine participants with moderate hearing loss and no prior hearing-aid use were randomly assigned to be sequentially fitted with both traditional and M&RIE receivers. The abbreviated profile of hearing aid benefit (APHAB) and word recognition score (WRS) were assessed. Audiological amplification was evaluated using real-ear measurements to determine whether a third in-ear microphone limits real-ear gain. <b>Results:</b> WRSs and APHAB scores showed no significant differences between the standard and M&RIE receivers. In addition, real-ear measurements across all frequencies and earplug types revealed no significant differences in real-ear insertion gain between the two receivers at a conversational level (65 dB SPL). <b>Conclusions:</b> The M&RIE provides amplification comparable to that of the standard receiver while preserving natural sound cues without significant audiological disadvantages.