Background: The diagnosis of Childhood Apraxia of Speech (CAS) remains heavily debated, and there is no agreement upon the etiology for the disorder. Whilst there is some consensus on the potential broad array of presenting features of children with CAS, only three key features are recognised as ubiquitous for diagnosis: 1) inconsistent error production on both consonants and vowels across repeated productions of syllables or words; 2) lengthened and impaired coarticulatory transitions between sounds and syllables; and 3) inappropriate prosody. Despite the typically severe and complex presentation of CAS, there is little evidence reported on intervention approaches for the disorder, perhaps as a result of the ongoing deliberation over etiology and diagnosis.
Objectives: The aim of this paper was to assess the efficacy of intervention delivered by Speech and Language Pathologists(s)/Speech and Language Therapists targeting CAS in children and adolescents.
Method: Several electronic databases were searched up to January 2007. The review considered randomised controlled trials (RCTs) and quasi-randomised studies of children aged 3 to 16 years with CAS, grouped by treatment types (e.g., perceptual and instrumentally-based biofeedback treatment techniques). Two authors independently assessed references identified from the searches and obtained full text versions of all potentially relevant articles.
Results: Of 825 titles and abstracts searched, only 31 abstracts appeared to meet inclusion criteria. The remaining 794 papers were excluded predominantly on the basis of not including participants with CAS (e.g., focused on other developmental speech disorders or adult acquired apraxia of speech), or for not being intervention studies (i.e. being diagnostic or descriptive). All 31 full text articles obtained were excluded following evaluation as they did not meet inclusion criteria on design.
Conclusion: The review demonstrates a critical lack of well controlled treatment studies addressing treatment efficacy for CAS, making it impossible for conclusions to be drawn about which interventions are most effective for treating CAS in children or adolescents.