Developmental phonological disorders. III: Long-term speech-sound normalization.
Prior articles in this series provide a descriptive profile of 178 children with developmental phonological disorders (Shriberg & Kwiatkowski, 1994) and predictive correlates of short-term speech-sound normalization in 54 children (Shriberg, Kwiatkowski, & Gruber, 1994). The present article reports findings from a study of 10 children with developmental phonological disorders whose progress was followed at least once yearly for 7 years. Analyses characterize the sequence, rates, and error patterns of long-term speech-sound normalization in relation to developmental perspectives on the nature of children's phonological disorders. Findings are interpreted to support the hypothesis of a critical period for speech-sound development, with long-term normalization of significant speech delay reaching a chronological age boundary at approximately 8.5 years.
Shriberg
L D
LD
Waisman Center on Mental Retardation and Human Development, University of Wisconsin-Madison 53705.
Gruber
F A
FA
Kwiatkowski
J
J
D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007804:Language Development; D007805:Language Development Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology* / Q000628:therapy; D008297:Male; D010699:Phonation; D011379:Prognosis; D012720:Severity of Illness Index; D013070:Speech Therapy; D013997:Time Factors; D016896:Treatment Outcome