Background and purpose: Speech intelligibility refers to how speech is understandable by listeners.  This study examined speech intelligibility in children (Persian native speakers) with spastic cerebral palsy aged 8-12 years old.

Materials and methods: A cross-sectional study was performed in 31dysarthric students (….. boys and …..girls)  in Tehran, 2014. A list of words and sentences were prepared and its content validity was examined. Speech samples were recorded when the participants repeated the words and sentences. The speech samples were transcribed by two groups of familiar and unfamiliar listeners (n=62).

Results: The mean scores for word and sentence intelligibility in familiar listeners were 64.25 and 74.9, respectively and 64.51 and 79.3 in unfamiliar listeners, respectively. The mean intelligibility scores were significantly higher in familiar listeners compared with unfamiliar listeners (P<0.001). Average sentence intelligibility score was found to be significantly higher compared with words (P<0.001). 

Conclusion: Intelligibility of the words was higher than moderate and sentences intelligibility was fair. Unfamiliar listeners were more precise in words and sentences detection. Listeners used context for better detection.