Effects of second language exposure on the integrated digits-in-noise test in Cantonese non-native speakers with normal hearing

OBJECTIVE: This study aimed to evaluate the effectiveness of the integrated digit-in-noise test (iDIN), which uses digit sequences of varying lengths as test materials, in assessing speech-in-noise recognition among non-native Cantonese speakers with normal hearing. DESIGN: A cross-sectional observational study was conducted involving native Mandarin speakers with Cantonese as a second language. Participants completed Cantonese and Mandarin versions of iDIN and the Cantonese Speech in Noise Test (HINT). In the iDIN, only the 2-, 3-, and 5-digit forward recall, as well as the 3-digit backward recall conditions, were administered. Data on language experience, proficiency, and exposure were collected through questionnaires. STUDY SAMPLE: Forty-seven participants (mean age 29.13 years) with normal hearing and Cantonese as a second language were recruited in Hong Kong. All had varying durations of Cantonese exposure, from