Classification of Children's Speech Sound Disorders
- Created on Saturday, 12 November 2011 15:42
- Updated on Friday, 15 March 2013 19:04
Approaches to Classification
Shriberg and colleagues' subtypes of Speech Sound Disorders (SSD) are based on genetic and environmantal risk factors (Shriberg, Potter & Strand, 2009). Dodd's approach is around linguistic profiling and linguistic subtypes. These and other classification systems are discussed by Bowen, 2009a, Chapter 2.
Clinicians tend to use a simplified, 'family friendly' approach in explaining to families how SSDs are classified. The example of a simplified approach that is included below is the one used by the author, and modified to suit individual families, over many years of clinical practice.
Note that within each classification system one or more types of SSD can co-occur (be present in the same child).
Subtypes of Speech Sound Disorders (SSD) Model
Shriberg, Potter & Strand (2009)
- Speech Delay-Genetic (SD-GEN)
- Speech Delay OME (SD-OME)
- Speech Delay-Developmental Psychosocial Involvement (SD-DPI)
- Motor Speech Disorder Apraxia of Speech (MSD-AOS)
- Motor Speech Disorder Dysarthria (MSD-DYS)
- Motor Speech Disorder Not Otherwise Specified (MSD-NOS)
- Speech Errors-Sibilants (SE-/s/
- Speech Errors-Rhotics (SE-/r/)
- Undifferentiated Speech Delay (USD)
- Undifferentiated SS Disorder (USSD)
Linguistic Profiling and Speech Subtypes Model
Dodd (1995, 2005) proposed a model with psycholinguistic underpinnings that is based primarily on linguistic profiling and speech subtypes. In it, specific speech subtypes are matched to discrete areas of psycholinguistic difficulty or breakdown that are ‘testable’ or ‘differentially diagnosable’. It embraces four subtypes that can occur at any age or stage of speech development, plus CAS. They are:
All phonological rules or processes evident in a child’s speech output are attested in typical development, but are characteristic of children younger than the child in question.
Consistent deviant phonological disorder
Children have co-occurring non-developmental or unusual errors and developmental rules or processes, with the presence of unusual processes signalling that the child has impaired understanding of the target phonological system.
Inconsistent Speech Disorder
Children exhibit delayed and non-developmental error types and variability of production of single word tokens ≥40%.
Children are unable to produce particular perceptually acceptable phones.
Childhood Apraxia of Speech
Children with CAS have ‘deviant’ surface speech production patterns that may sound similar to those of children with inconsistent speech disorder, but they are different in proposed level of breakdown and in symptomatology. Note that Dodd usses the term 'DVD' in the first edition of her book and 'CAS' in the 2005 (second) edition.
Family Friendly Classification
This involves difficulty producing one or just a few speech sounds, e.g., /s/, /z/, /l/, /r/. Another term for this is Functional Speech Disorder.
This involves persistence of errors that are typical of younger children’s speech, e.g., producing ‘front sounds’ at the back of the mouth (key = tea, guy = dye) or omitting consonants (boot = boo, snow = no), or omitting syllables (Thomas = Tos).
Motor Speech Disorders
These include speech difficulties due to Childhood Apraxia of Speech (difficulty planning movements for speech) and the dysarthrias (difficulty making movements for speech due to paralysis).
Structurally-based Speech Sound Disorders
These include speech difficulties associated with head/facial anatomy differences (e.g., cleft palate, misaligned teeth, or the craniofacial differences associated with some syndromes).
Speech Sound Disorders associated with syndromes and conditions
These include speech difficulties associated with syndromes such as Down syndrome, metabolic conditions such as galactosemia, and sensory conditions such as hearing impairment.
Citing this Article
Cite this article as: Bowen, C. (2011). Classification of children's speech sound disorders. Retrieved from www.speech-language-therapy.com/index.php?option=com_content&view=article&id=45:classification&catid=11:admin&Itemid=121 on [insert the date that you accessed the file here].