Reliability and validity of an online auditory aptitude testing platform: A validation study of formant discrimination tasks

Individual differences in auditory processing abilities constrain second language (L2) speech learning outcomes. This study developed and validated three versions of an auditory discrimination test designed to measure formant perception acuity, a domain-general auditory ability relevant to L2 learning. We compared Standard (adaptive staircase method), Gamified (staircase with game components), and QUEST (Bayesian adaptive method) versions in terms of threshold estimation, test–retest reliability, and their predictive validity for L2 vowel discrimination. In 2 sessions, 114 Mandarin speakers completed all 3 test versions and an English vowel perception task. All versions yielded comparable thresholds. The Gamified version demonstrated the highest test–retest reliability, followed by the Standard version; the QUEST version showed the least consistency. The relationship between formant acuity and L2 vowel discrimination was statistically indistinguishable across versions. The results indicate that gamification elements can enhance measurement consistency without compromising validity. This open-access platform offers researchers a validated, accessible tool for measuring formant discrimination acuity, a key component of auditory processing in L2 acquisition.