Predictability of sentences used in the assessment of speech intelligibility in dysarthria.

PURPOSE To analyze the predictability of sentences used in the protocol for the assessment of intelligibility of dysarthric speech. METHODS A cross-sectional study was conducted in 120 volunteers divided randomly into four groups of 30 individuals.Based on the list of 25 sentences from the protocol, four versions of lists were elaborated. In each version, a different target word was omitted from the sentences. Each group of participants completed a different list version by graphically filling in the blanks with the first word that came to mind, while keeping the sentences coherent. Statistical analyses were carried out to classify sentences according to their predictability, to compare predictability of the words in each sentence, and to compare the different list versions. RESULTS Three sentences presented high predictability; seven, average predictability; and fifteen, low predictability. Differences in the predictability of target words were found in 84% of the sentences (p ≤ 0.0054). The comparison of list versions revealed that version 1 differed from the others (p ≤ 0.002), and was less predictable. CONCLUSION Low predictability sentences predominated in the protocol for assessment of speech intelligibility used in this study, suggesting that these sentences can be used reliably for assessing intelligibility. Analysis of intelligibility in sentences based on target words can be used in clinical practice, especially when the predictability of the sentences is known.