Sentence intelligibility as a function of key word selection

The purpose of this study was to investigate the relationship between word predictability and sentence intelligibility. This relationship was examined by comparing intelligibility scores obtained with frequency filtered sentences (CID Sentence Lists B and D and Revised List C) which were scored using key words empirically determined to be representative of 3 different degrees of predictability. It was hypothesized that the scores obtained would be a function of the predictability status of the key words used in scoring. Results indicated significant differences between the 3 scoring procedures for each sentence list under 2 filtering conditions (420 Hz and 360 Hz low pass) and these differences were in the hypothesized direction. The results suggest that use of 'easy to predict' words for scoring purposes will increase sentence intelligibility scores, while use of 'difficult to predict' words will depress scores. It was concluded that word predictability is a factor influencing sentence intelligibility and that careful selection of key words, based on their predictability status, is a method of controlling or influencing the intelligibility of sentences.