Assessing the Homogeneity of Audibility of Pediatric Word and Sentence Corpus in Tamil

Background and Objectives: The aim of this study was to assess the homogeneity of the audibility of word and sentence corpora for use in the development of speech audiometry test tools in Tamil.Materials and Methods: A Tamil corpus (675 words and 195 sentences) was compiled from books, magazines, and novels of children aged five to ten years. A female speaker was chosen to record the corpus based on expert ratings. All recorded contents were root mean square–normalized using Adobe Audition 3.0. The recorded material was randomly placed into 27-word lists (25 words/list) and 20-sentence lists for psychometric assessment. Speech perception testing was done at five intensities (0, 10, 20, 30, and 40 dB SL; referenced to pure-tone average) in 20 adults with normal hearing.Results: Analysis of variance indicated significant differences (p<0.01) in speech perception scores as a function of intensity for all words and sentences. A logistic regression model was fitted to estimate the thresholds (i.e., the intensity level at which 50% scores were obtained) from the curve, which was observed around 10.12 dB SL for the words and 11.77 dB SL for the sentences.Conclusions: All words and sentences in the pediatric Tamil corpus were observed to be homogenous in audibility. Hence, all words and sentences can be utilized for developing an assessment tool process, as well as in subsequent clinical assessments.