Principal Findings
REMs, WRS
This study used a noninferiority study design to compare the audiological performance between an SHAA and a conventional HA. The SHAA did not show noninferiority to the HA in the WRS test, which was the primary measurement used in the original study. However, the SHAA showed feasibility in some users, especially in unaided conditions and for the amplification of soft sounds. In this study, 63 participants were screened and 38 finished the study. The objective audiological performance was evaluated using the warble-tone hearing test, the WRS test, REMs, and the HINT, and subjective satisfaction was evaluated using the APHAB and IOI-HA questionnaires. The aided hearing thresholds for the SHAA were 20-60 dB, from low to high frequencies. Although the SHAA group showed a lower gain at the 1000- to 8000-Hz levels than the HA group, it showed gains similar to those of the HA group at low frequencies. The REMs results at 75 dB, as well as the common speaking levels of 55 and 65 dB, indicated that the HA group showed greater gains in the middle-to-high frequencies than the SHAA group. One-third (14/38, 37%) of the SHAA group showed slight improvements in WRS. However, most SHAA users (24/38, 63%) showed no difference in their WRS compared to the unaided group. The HA group showed significantly better audiological performance than the unaided and SHAA groups in all HINT situations. The HA group showed the highest scores in the IOI-HA, but the SHAA users also showed significantly greater improvement than the unaided group. A comparison of individuals in the SHAA group between unaided and aided conditions found that 37% (14/38), 42% (16/38), 24% (9/38), and 32% (12/38) of users showed improvements in the ease of communication, reverberation, background, and aversiveness of sound subscales of the APHAB, respectively.