What is speech and language impairment (SLI)?

The common SLI amongst students are categorised into four major types:

(1) Articulation problem

  • Articulation problem refers to incorrect pronunciation of students that causes confusion of speech, for example,  saying “duck” as “guck” (/dʌk/ -> [gʌk]); and “taking lesson” as “taking lechon” (/’lɛsən/ -> [‘lɛʧən]) or “taking leton” (/’lɛsən/ -> [‘lɛtən]).
  • Congenital physical defects, such as hearing impairment, cleft lip, cleft palate or cerebral palsy, etc., are factors causing articulation problem.
  • Other factors include developmental delay.


(2) Language problem

  • Students with difficulties in comprehension may merely be able to grasp part of the meanings in a long or complex sentence.  They often fail to comprehend the message fully, which leads to communication breakdown.
  • Students with expression difficulties, owing to weak sentence organisation skills or inappropriate use of vocabulary, may have difficulties in expressing.   People may find it difficult to understand their messages.
  • Factors leading to language impairment include language developmental delay, learning difficulties, intellectual disability, exposure to environment with inadequate language stimulations, or autism spectrum disorders.


(3) Fluency problem

  • Fluency problem is also known as stuttering.  The symptoms include repetition of some words or syllables, prolongation of phonemes, speech rate being too fast or too slow, and speech blocks.
  • Stuttering may be caused by psychological, physical, genetic factors, etc., or regarded as transient manifestations along the development.


(4) Voice problem

  • Voice problem is commonly caused by overuse or incorrect use of vocal cords, which leads to hoarseness of voice or even loss of voice.  Students usually shout and yell during recess or play time, which causes damage to vocal cords and even the growth of vocal polyps, and results in hoarse voice.
  • Neuropathological diseases or emotional disturbance are also factors leading to voice problem.
  • Long-term disorders in respiratory organs and defects in articulatory organs and structures (such as cleft lip and palate) will also cause hyper-nasality or disorder of pitch.


If I suspect that my child might have SLI, I should…

…communicate with teachers first. With my consent, the school will record the problems and difficulties of my child by filling in the “Observation Checklist for Identifying Students with Speech and Language Impairment in Primary Schools (For Teachers)” / “Observation Checklist for Identifying Students with Speech and Language Impairment in Secondary Schools (For Teachers)” provided by the Speech Therapy Service Section of the Education Bureau, or a corresponding identification checklist provided by the school-based speech therapist (SBST).  The school will also refer my child to the SBST for assessment and follow-up services.


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