Age-related maturation of antiphasic Arabic Digits-in-Noise thresholds in children

Purpose
Paediatric data in Arabic are largely absent from the Digits-In-Noise (DIN) literature, representing a critical gap in knowledge. This study aims to describe the developmental patterns of Arabic antiphasic DIN thresholds in children aged 5–17 years, determine the age at which DIN thresholds converge with adult levels, and characterise age-related changes in task performance metrics, including response time, response time variability, psychometric function slopes, and digit-position effects.

Method
Audiometrically normal Arabic-speaking children (n = 65) and adults (n = 33) completed antiphasic DIN testing. Age-related trends were analysed to identify the onset of adult-like performance, with thresholds beyond this point compared to adults using equivalence testing. Exploratory analyses estimated developmental inflection points via segmented regression and reported effect sizes with confidence intervals. Further supplementary analyses examined age-related trends in response times, response time variability, psychometric slopes, and effects of digit-position (1/2/3) on response accuracy.

Results
Most five-year-olds were unable to complete the DIN task, but thresholds approached adult-like levels from age 10, with evidence of equivalence from age 13 within predefined bounds. Exploratory segmented regression suggested inflection points near age 6 and age 10, although confidence intervals were wide for the latter. Increasing age was linked to faster and more consistent responses with less consistent evidence for changes in psychometric slope. Response accuracy in the youngest children varied by digit position.

Conclusions
Findings indicate rapid maturation of antiphasic Arabic DIN performance, with task acquisition emerging in early school age and near-adult thresholds observed in early adolescence. The observed developmental pattern likely reflects a combination of auditory and task-related cognitive and linguistic factors; however, these processes were not directly assessed in the present study and should be interpreted cautiously. These results provide provisional developmental reference points and require validation and test optimisation in children with hearing loss before paediatric hearing screening implementation.