ACQ Vol 12 no 1 2010

Motor speech disorders

Management of acquired motor speech disorder in children A practical reflection on the evidence Angela. T. Morgan

The term “acquired brain injury” (ABI) encompasses many debilitating neurological aetiologies, including stroke, encephalitis, traumatic brain injury, and brain tumour. Dysarthria is one communication impairment associated with ABI. In contrast with the adult field, limited data are available on the incidence, clinical features, and treatment techniques for acquired dysarthria in childhood. The aim of the present report is to provide an overview of current evidence regarding assessment and treatment of dysarthria associated with childhood ABI. A practically oriented discussion of what the evidence means for clinicians working in acute or rehabilitative practice is provided. Assessment and diagnosis A recent survey of 51 speech-language pathologists from 26 major paediatric rehabilitation centres across Australia, New Zealand, the United Kingdom, and Ireland explored current motor speech assessment practices (Morgan & Skeat, in press). The majority of clinicians (67%) reported that they were not satisfied with current motor speech assessments for children with ABI. The most commonly used standardised assessment tool was the Frenchay Dysarthria Assessment (Enderby, 1983) used by 74% of the group. The most commonly used informal diagnostic approach was the MAYO clinic diagnostic classification (Darley, Aronson & Brown, 1975; Duffy, 2005), used by 67% of clinicians surveyed. The limitations of using these tools with children are obvious, in that: i) both tools were designed for adults; and ii) only the Frenchay is standardised, yet based on adult performances only, making the psychometric data invalid for extrapolation to a paediatric population. Why are paediatric clinicians relying on adult-based tests? In short, because there are no tests available that have been standardised or developed specifically for children with acquired dysarthria.

speech field to find alternative tools. The following section considers commercially and non-commercially available tools. Commercial assessment tools There are a number of commercially available standardised tests that purport to assess “motor speech” in children, implying that they assess both dysarthria and dyspraxia. Anecdotally however, clinical observations may lead one to surmise that the majority of paediatric motor speech assessments have a particular bent towards childhood apraxia of speech (CAS). In fact, this CAS bias was recently confirmed, based on data in a review paper by McCauley and Strand (2008). The authors evaluated the content and psychometric characteristics of standardised tests of nonverbal oral and speech motor performance in children. Criterion for inclusion of tests for review were that the test was: a) standardised; b) included young children (at or below elementary school age), c) addressed non-verbal oral motor/ motor speech function, and d) available in July 2006 through a commercial source. Tests that were only focused on oral mechanism structure or sound system analyses were excluded. Only six of the 22 identified assessments met criterion: i) Apraxia Profile (Hickman, 1997); ii) Kaufman Speech Praxis Test for Children (Kaufman, 1995); iii) Oral Speech Mechanism Screening Examination 3rd Ed. (St Louis & Ruscello, 2000); iv) Screening Test for Developmental Apraxia of Speech – 2nd Ed. (Blakely, 2001); v) Verbal Dyspraxia Profile (Jelm, 2001); and vi) Verbal Motor Production Assessment for Children (Hayden & Square, 1999). Even from the titles of these assessments, it is obvious that four of the six tests focus predominantly, if not exclusively, on CAS. Overall conclusions from the review were that the tests varied markedly in both content and the methods of test interpretation (McCauley & Strand, 2008). Few tests documented reliability or validity data, even when this information may have been generated during the test’s development (McCauley & Strand, 2008). The VMPAC was the only assessment to provide “adequately described” normative data. It also came closest to meeting operational definitions for test-retest and inter-examiner reliability data, but did not fully meet them due to a lack of statistical detail. The VMPAC was also the only test to meet any of the three operational definitions for validation. Specifically, the VMPAC

This article has been peer- reviewed Keywords apraxia brain injury child dysarthria motor speech

Angela. T. Morgan

Current evidence guiding assessment approaches

In the absence of an ABI specific paediatric dysarthria assessment, we must look to the broader paediatric motor

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ACQ Volume 12, Number 1 2010

ACQ uiring knowledge in speech, language and hearing