Phonological skills of children with specific expressive language impairment (SLI-E): outcome at age 3

Naturalistic speech samples of 29 3-year-olds diagnosed with specific expressive language delay (SU-E) were compared to those produced by 19 age-matched normally developing peers in order to determine their improvement in phonological skills since age 2, when Rescorla and Ratner (1996) studied them. Specifically, the groups were compared with regard to vocalization rate, verbalizations, fully intelligible utterances, phonetic inventories, percentages of consonants correct (PCC), phonological processes, and mean length of utterance (MLU). Results revealed that there was no significant difference between the groups in their numbers of vocalizations (as there had been at age 2), although there continued to be differences in their phonetic inventories, PCC scores, and overall intelligibility. These findings suggest that at age 2 the children with SU-E were not only less phonologically skilled but less talkative, whereas by age 3 they were equally vocal. Analysis of the phonetic inventories of the children demonstrated that for most consonants, the SLI-E group followed the some pattern of development as the comparison children, but more of the normally developing group had productive control of each consonant, consistent with findings of Rescorla and Ratner. There continued to be differences in intelligibility as measured by rates of verbalization (those utterances with at least one intelligible word) and fully intelligible utterances. Using these measures, we found that approximately half the SU-E children had caught up with their normally developing peers in terms of articulation, whereas half of them continued to be significantly delayed. Finally, although some of the late-bloomer group had caught up to the comparison children in language skills, as measured by MLU, many had not, suggesting that there was a tendency for the children to catch up in some articulation skills before catching up in language abilities.