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Speech and language therapy interventions for children with primary speech and language delay or disorder

Additional Info

  • Authors: James Law, Zoe Garrett, Chad Nye
  • Published date: 2005-11-13
  • Coordinating group(s): Social Welfare
  • Type of document: Review, User abstract
  • See the full review: https://onlinelibrary.wiley.com/doi/10.4073/csr.2005.5
  • English:

    This article is based on the Campbell Review: Law J, Garett Z, Nye C: Speech and language therapy interventions for children with primary speech and language delay or disorder. The Campbell Collaboration 2003. This article is written by the Nordic Campbell Centre. The article has been approved by the authors of the review. Published October 2006

    Speech and language therapy can help children with expressive phonological and expressive vocabulary difficulties

    It is important to offer help to children with expressive phonological and expressive vocabulary difficulties. If these problems are not addressed, this can have serious implications for their general well-being, development and learning. Speech and language therapy can help these children.

    Research has shown that it can be beneficial to involve normal language peers in the therapy process. They can serve as positive role models. This is the finding of a Campbell Review which also shows that it has no bearing on the effectiveness of language and speech therapy whether the children participate in groups or individually.

    Language and life quality

    International research has shown that approx. six per cent of all children have general speech and language difficulties. This may involve receptive and expressive vocabulary difficulties, difficulty in constructing sentences (syntax) and expressive phonological difficulties. For a number of these children, these problems will have no lasting effect on their future development. But for 30-60 per cent, these difficulties will continue into their adolescence and on into adult life. For these children, receptive and expressive vocabulary difficulties and expressive and receptive phonological difficulties may have a negative effect on their quality of life in the form of poor school achievement, a lack of social skills and emotional and behavioural problems.

    Speech and language therapy works

    This Campbell Review concludes, on the basis of the available international studies in this field, that speech and language therapy generally has a positive effect on children with expressive phonological difficulties. The therapy also helps children who have a problem with their active vocabulary, i.e. children who have difficulty in using words they understand. Children, who have difficulty with active vocabulary alone, but no problem understanding and acquiring language, also benefit from speech and language therapy.

    Speech and language therapy for children who have difficulty in applying grammar and constructing sentences is, however, only thought to have a positive effect if the child does not have other significant receptive speech and language difficulties.

    It has no bearing on the effectiveness of speech and language therapy whether the children participate in groups or individually. The effectiveness of speech and language therapy focussing on sounds is the same whether carried out by a professional or a parent who has been trained to administer speech and language therapy. But it has been shown to have a positive effect if normal language peers are allowed to participate in the speech and language therapy.

    Finally there is some indication that the effectiveness of speech and language therapy is greater if it takes place over a period of more than eight weeks.

    Which children participated in the study?

    This Campbell Review is based on studies of children and adolescents with a diagnosis of primary speech and language delay/disorder, i.e. their difficulties cannot be accounted for by a condition such as autism, hearing impairment or social problems. The oldest child who participated in one of the studies was fifteen. Children with stutters or learned misarticulations were excluded from this review.

    1,500 children in 36 different studies

    The conclusions of the review are based on the results of a large number of studies, all written in English. Thirty-six studies were found, based on a total of 1,500 children involved in thirty-three randomised controlled trials.

    The thirty-six studies were chosen because they fulfilled the Campbell Review’s inclusion criteria with regards to who, what and why, and because the studies also complied with the minimum quality requirements of the review.

    Speech and language therapy in one

    The review does not differentiate between different types of speech and language therapy. The most important criterion is that the therapy should have the objective of improving the child’s understanding and pronunciation of sounds. Therapy that focuses on the treatment of receptive speech and language skills may be more resistant to improvement

    What success criteria does the review there focus on?

    The review assesses the effectiveness of speech and language therapy on the basis of the following measurements of success:

    1. Improved use and understanding of speech.
    2. Improved use and understanding of words (vocabulary).
    3. Improved grammar and sentence construction, where differentiation is made between what the child knows and understands and what he/she is able to use.

    Consequences for research

    Even though speech and language therapy can help children with expressive phonological difficulties and expressive vocabulary difficulties, there is a general need for more research in this area. The Campbell Review emphasizes, for example, the need to clearly define the interventions in advance. This would make it easier to explain and understand any variations in the results.

    It has also been suggested that more research should be carried out into how the results of the intervention of therapy in the case of learning difficulties can be optimised. There is also a need for greater knowledge about when it is the best time to initiate the treatment; as early as possible, or when the child is mature enough for change?

Select language:

This article is based on the Campbell Review: Law J, Garett Z, Nye C: Speech and language therapy interventions for children with primary speech and language delay or disorder. The Campbell Collaboration 2003. This article is written by the Nordic Campbell Centre. The article has been approved by the authors of the review. Published October 2006

Speech and language therapy can help children with expressive phonological and expressive vocabulary difficulties

It is important to offer help to children with expressive phonological and expressive vocabulary difficulties. If these problems are not addressed, this can have serious implications for their general well-being, development and learning. Speech and language therapy can help these children.

Research has shown that it can be beneficial to involve normal language peers in the therapy process. They can serve as positive role models. This is the finding of a Campbell Review which also shows that it has no bearing on the effectiveness of language and speech therapy whether the children participate in groups or individually.

Language and life quality

International research has shown that approx. six per cent of all children have general speech and language difficulties. This may involve receptive and expressive vocabulary difficulties, difficulty in constructing sentences (syntax) and expressive phonological difficulties. For a number of these children, these problems will have no lasting effect on their future development. But for 30-60 per cent, these difficulties will continue into their adolescence and on into adult life. For these children, receptive and expressive vocabulary difficulties and expressive and receptive phonological difficulties may have a negative effect on their quality of life in the form of poor school achievement, a lack of social skills and emotional and behavioural problems.

Speech and language therapy works

This Campbell Review concludes, on the basis of the available international studies in this field, that speech and language therapy generally has a positive effect on children with expressive phonological difficulties. The therapy also helps children who have a problem with their active vocabulary, i.e. children who have difficulty in using words they understand. Children, who have difficulty with active vocabulary alone, but no problem understanding and acquiring language, also benefit from speech and language therapy.

Speech and language therapy for children who have difficulty in applying grammar and constructing sentences is, however, only thought to have a positive effect if the child does not have other significant receptive speech and language difficulties.

It has no bearing on the effectiveness of speech and language therapy whether the children participate in groups or individually. The effectiveness of speech and language therapy focussing on sounds is the same whether carried out by a professional or a parent who has been trained to administer speech and language therapy. But it has been shown to have a positive effect if normal language peers are allowed to participate in the speech and language therapy.

Finally there is some indication that the effectiveness of speech and language therapy is greater if it takes place over a period of more than eight weeks.

Which children participated in the study?

This Campbell Review is based on studies of children and adolescents with a diagnosis of primary speech and language delay/disorder, i.e. their difficulties cannot be accounted for by a condition such as autism, hearing impairment or social problems. The oldest child who participated in one of the studies was fifteen. Children with stutters or learned misarticulations were excluded from this review.

1,500 children in 36 different studies

The conclusions of the review are based on the results of a large number of studies, all written in English. Thirty-six studies were found, based on a total of 1,500 children involved in thirty-three randomised controlled trials.

The thirty-six studies were chosen because they fulfilled the Campbell Review’s inclusion criteria with regards to who, what and why, and because the studies also complied with the minimum quality requirements of the review.

Speech and language therapy in one

The review does not differentiate between different types of speech and language therapy. The most important criterion is that the therapy should have the objective of improving the child’s understanding and pronunciation of sounds. Therapy that focuses on the treatment of receptive speech and language skills may be more resistant to improvement

What success criteria does the review there focus on?

The review assesses the effectiveness of speech and language therapy on the basis of the following measurements of success:

  1. Improved use and understanding of speech.
  2. Improved use and understanding of words (vocabulary).
  3. Improved grammar and sentence construction, where differentiation is made between what the child knows and understands and what he/she is able to use.

Consequences for research

Even though speech and language therapy can help children with expressive phonological difficulties and expressive vocabulary difficulties, there is a general need for more research in this area. The Campbell Review emphasizes, for example, the need to clearly define the interventions in advance. This would make it easier to explain and understand any variations in the results.

It has also been suggested that more research should be carried out into how the results of the intervention of therapy in the case of learning difficulties can be optimised. There is also a need for greater knowledge about when it is the best time to initiate the treatment; as early as possible, or when the child is mature enough for change?

See the full review

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