Helen Grech (University of Malta) Assessment and Diagnosis of Sub-Types of Speech Disorders in Children Sound Difficulties in the Maltese Speech Disorders in Assessment Maltese Context Helen Grech (University of Malta) ISHLA February 2017

OUTLINE Prevalence Classification of Speech Disorders Speech Processing Model Identified sub-groups of Speech Disorder Deficits in the Speech Processing Chain Characteristics of Sub-types of Speech Disorder

Children with Speech Sound Difficulties (SSD) High % of SLPs case load includes children with SSD In Middlesborough, UK, around 30% of children referred for therapy were those with SSD (Broomfield & Dodd, 2004) Prevalence of SSD reported 2.3-24.6% for ‘speech delay’ only (Law et al, 2000) Mcleod & Baker (2017) report studies with diverse prevalence of children with SSD (with & without comorbidity)

Different approaches for describing speech difficulties exist. There is no agreed classification to date. The need for a harmonised classification system for developmental speech disorders is acknowledged universally e.g., Shriberg (2002); US National Institute of Health (2003); Dodd (2005).

Classifying by Aetiology (e.g., Shriberg, 2002; Shriberg et al, 2010) Often no identifiable cause or difficult to establish 1 cause Shriberg (2002) claims that speech disorder of unknown origin is possibly genetically linked Shriberg et al (2010) reports that classification systems based on biological phenotypes is needed given the advances in genomics Does this determine the nature/extent of the disorder & clinical management?

Linguistic Typology (e.g., Grunwell, 1985) Discribes nature/extent of speech difficulties No possible explanation to the impairment is given Treating the symptoms & not underlying difficulties

Pycholinguistic Approach (e.g., Stackhouse & Wells, 1997) Mapping interactions of input, cognitive-linguistic mental processes & output Identifies strengths & weaknesses in speech-processing chain Lengthy process for diagnosis; child is claimed as unique & fails to identify sub-groups

Sub-groups of SSD (Dodd, 1995; 2005) Links surface error patterns with underlying deficits Specific intervention approaches used depending on claimed deficit Cross-linguistic case studies supporting evidence & effectiveness of therapy

Phonological impairment Inconsistent speech disorder McLeod & Baker (2017) Types of SSD Phonological impairment Inconsistent speech disorder Articulation impairment Childhood apraxia of speech Childhood dysarthria Base sub-grouping of SSD on the speech processing chain indicating possible difficulties at the following levels: Perception Articulation/Motor Phonological representation Organisation

Model of Speech-processing Chain From Dodd B. &. McCormack, P. (1995). A model of speech processing for differential diagnosis of phonological disorders. In B. Dodd (Ed.) Differential Diagnosis and Treatment of Children with Speech Disorders (p. 65). London:Whurr Pub.

Model of Speech-processing Chain From Dodd B. &. McCormack, P. (1995). A model of speech processing for differential diagnosis of phonological disorders. In B. Dodd (Ed.) Differential Diagnosis and Treatment of Children with Speech Disorders (p. 65). London:Whurr Pub.

What to Assess? Anatomical & physiological Phonetic Phonological Developmental

Subtypes of Speech Disorder (Dodd,1995) Articulation disorder Delayed phonological development Consistent deviant disorder Inconsistent disorder Others (such as dyspraxia) 5

Articulation Disorder What to assess??? Impaired ability to pronounce any individual speech sounds in words, CV syllables or in isolation, on imitation.

‘Errors’ characteristic of younger normally developing children Delayed Phonological Development ‘Errors’ characteristic of younger normally developing children What to assess???

Consistently Used Non-developmental Error Patterns May also exhibit one or more delayed error patterns Exhibit difficulties with phonological awareness Associated with later literacy difficulties What to assess???

Production of same lexical item inconsistently Inconsistent Errors Production of same lexical item inconsistently (in absence of oro-motor difficulties such as groping or an impaired ability to imitate oral gestures and words) What to assess???

Characteristics of DVD (Ozanne, 1995) CHILDREN WHO EXHIBIT DIFFICULTIES IN: PHONOLOGICAL PLANNING PHONETIC PROGRAMMING OROMOTOR & SPEECH-MOTOR PROGRAMME IMPLEMENTATION Those exhibiting deficits at 1-2 levels should not be classified as having DVD.

Phonological Planning VOWEL ERRORS MORE ERRORS IN POLYSYLLABIC WORDS MORE ERRORS IN PHRASES LIMITED USE OF RULES/PROCESSES POOR PHONOTACTICS INCONSISTENT ARTICULATION

Phonetic Programming GROPING CONSONANT DELETION VOLUNTARY VERSUS INVOLUNTARY CONTROL

Oro/Speech Motor Programming DDK RATE DDK SEQUENCES POOR OROMOTOR SKILLS

Intervention Approaches Whole language approach Phonologically based approach Metaphon therapy (Dean et al, 1995) Maximal contrast approach (Gierut, 1989) Core vocabulary approach PROMPT therapy Parents and children together (PACT) collaborative approach to phonological therapy 12

Phonological contrast Comparison of Intervention Approaches (Dodd, 2004) S = SUCCESSFUL; US = UNSUCCESSFUL; NT = NOT TESTED Approach Articulation Delay Consistent Inconsistent Single speech sound S NT US Phonological contrast Core vocabulary Whole language