The Korean digits-in-noise test clinically complements the Korean hearing-in-noise test

Abstract

Difficulty understanding speech-in-noise (SiN) is a prominent early deficit in sensorineural hearing loss not fully explainable by an elevated hearing threshold, thereby highlighting the need to efficiently measure the important aspects of everyday listening difficulties. We compared the Korean Digits-in-Noise Test (K-DiNT) and the Korean Hearing-in-Noise Test (K-HiNT) in capturing the effects of hearing loss (HL) severity and spatial separation on SiN perception and examined the relationship between the K-DiNT and K-HiNT outcomes across spatial listening conditions. Speech reception thresholds increased with greater HL across all conditions, while spatial separation improved SiN performance in both tests. This implies spatial release from masking, with the K-DiNT yielding a substantially larger spatial benefit than the K-HiNT. The outcomes of the two tests were strongly correlated across all listening conditions, with the highest correlation for the K-HiNT composite score comprising the noise-front, noise-left, and noise-right conditions. These findings indicate that the K-DiNT captures key aspects of SiN perception under various spatial listening conditions despite differences in stimulus format and linguistic demands between the two tests. Given its short testing time, minimal linguistic demands, and smartphone compatibility, the K-DiNT is a practical and accessible tool for assessing SiN perception and demonstrably complements sentence-based testing.