The development of Thai monosyllabic word and picture lists applicable to interactive speech audiometry in preschoolers

Interactive speech audiometry is the assessment of speech comprehension and phonological discrimination through automated means. In order for the performance of such assessments in preschoolers to be successful, the employed list of words and pictures must be easily recognized both linguistically and visually. That is, the children must be able to easily associate the sound they hear with the picture they see with a high degree of certainty. To this end, a Thai monosyllabic word and picture list called NCU-20 (NECTEC-CU-20) is proposed. The word lists for Thai vowel and consonant hearing tests are designed with an awareness of phonetic environments. Regarding Thai vowels, both monophthongs and diphthongs, with all qualities and quantities, are examined. Initial consonants are categorized based on places and manners of articulation. The effectiveness of the list is objectively and subjectively verified through Thai Textbook Corpus, Thai National Corpus, Zipf scores, a listening test of preschoolers with normal hearing, and our proposed ranking systems referred to as Tier-1^st, Tier-3/3, and Overall Tier. The final suggested word and picture list comprises 45 items (words) covering 35 vowels and consonant groups in the Thai Language.