Purpose: To present a systematic review of single-case experimental treatment studies for childhood apraxia of speech (CAS).
Method: A search of 9 databases was used to find peer-reviewed treatment articles from 1970 to 2012 of all levels of evidence with published communication outcomes for children with CAS. Improvement rate differences (IRDs) were calculated for articles with replicated (n > 1), statistically compared treatment and generalization evidence.
Results: Forty-two articles representing Phase I and II single-case experimental designs (SCEDs; n = 23) or case series or description studies ( n = 19) were analyzed. Six articles showed high CAS diagnosis confidence. Of the 13 approaches within the 23 SCED articles, treatments were primarily for speech motor skills ( n = 6), linguistic skills ( n = 5), or augmentative and alternative communication ( n = 2). Most participants responded positively to treatment, but only 7 of 13 approaches in SCED studies reported maintenance and/or generalization of treatment effects. Three approaches had preponderant evidence (Smith, 1981). IRD effect sizes were calculated for Integral Stimulation/Dynamic Temporal and Tactile Cueing, Rapid Syllable Transition Treatment, and Integrated Phonological Awareness Intervention.
Conclusions: At least 3 treatments have sufficient evidence for Phase III trials and interim clinical practice. In the future, efficacy needs to be established via maintenance and generalization measures.