PTA₄: the four-frequency (0.5, 1, 2, and 4 kHz) pure-tone average thresholds on pure tone audiogram; WRS: word recognition score.

Fig. 1. Box-plots of differences in the hearing thresholds according to three outcomes of hearing-aid use (successful users vs. intermittent users vs. failed users). The hearing threshold at 1 Hz for the better ear was significantly different between successful users and intermittent users in the cases with UHL, shown in figure B.

Fig. 2. Box-plots of differences in hearing thresholds according to two outcomes of hearing-aid use (successful and intermittent users vs. failed users). There was no frequency that differed significantly between two outcomes.

Fig. 3. Comparison by the etiology of hearing loss according to the thresholds and outcomes of hearing-aid use compared using three outcomes (successful users versus intermittent users versus failed users) and two outcomes (successful-intermittent users versus failed users).

S, successful users; I, intermittent users, SI, successful-intermittent users; F, failed users.