In light of the proposal that a ratio of the maximum duration of sustained /s/ to /z/ sounds may be useful in determining the possible contributions of the respiratory and vocal mechanisms to a disordered voice, a study of /s/ and /z/ maximum phoneme duration in normal five-, seven-, and nine-year-olds was conducted. (Author/DLS)

This study examined the interaction of ambient frequency and feature complexity in the diphthong errors produced by 13 Cantonese-speaking children with phonological disorders. Perceptual analysis of 611 diphthongs identified those most frequently and least frequently in error. Suggested treatment guidelines include consideration of three factors:…