Speech therapy for children with dysarthria ac quired before three years of age

The review question

This review aimed to investigate if therapy is generally effective for children with dysarthria acquired early in life, and if certain types of therapy may be better than others.


Dysarthria is a speech disorder linked to difficulties controlling the muscles needed for speaking. Children with dysarthria often have shallow, irregular breathing which creates difficulties in generating sufficient breath to support speech. They have low pitched, breathy or harsh voices, nasalised speech and very poor pronunciation. Together, these difficulties make the children's speech difficult to understand. Dysarthria is caused by neurological impairment and can arise early in children's lives, from neurological damage sustained before, during or after birth, such as in cerebral palsy, or in early childhood through traumatic brain injury or neurological disease. Communication difficulties have a profound impact on children’s development. They reduce the quality of life of children with cerebral palsy and place children at risk of social exclusion, educational failure and later unemployment. Speech and language therapy aims to help children to control the movements for breathing and speech and so become more intelligible.

Study characteristics

We found no randomised controlled trials or controlled group studies which investigate the effects of speech and language therapy to improve the speech of children with dysarthria acquired below three years of age.

Key results

Small, observational studies have suggested that, for some children, therapy might have been associated with positive changes in intelligibility and clarity of voice. Rigorous research, using randomised controlled trials, is needed to evaluate if therapy can help children to increase the intelligibility of their speech and if enhanced intelligibility increases children's participation in social and educational activities and their quality of life.

Authors' conclusions: 

This review found no evidence from randomised trials of the effectiveness of speech and language therapy interventions to improve the speech of children with early acquired dysarthria. Rigorous, fully powered randomised controlled trials are needed to investigate if the positive changes in children's speech observed in phase I and phase II studies are generalisable to the population of children with early acquired dysarthria served by speech and language therapy services. Research should examine change in children's speech production and intelligibility. It must also investigate children's participation in social and educational activities, and their quality of life, as well as the cost and acceptability of interventions.

Read the full abstract...

Children with motor impairments often have the motor speech disorder dysarthria, a condition which effects the tone, strength and co-ordination of any or all of the muscles used for speech. Resulting speech difficulties can range from mild, with slightly slurred articulation and breathy voice, to profound, with an inability to produce any recognisable words. Children with dysarthria are often prescribed communication aids to supplement their natural forms of communication. However, there is variation in practice regarding the provision of therapy focusing on voice and speech production. Descriptive studies have suggested that therapy may improve speech, but its effectiveness has not been evaluated.


To assess whether any speech and language therapy intervention aimed at improving the speech of children with dysarthria is more effective in increasing children's speech intelligibility or communicative participation than no intervention at all , and to compare the efficacy of individual types of speech language therapy in improving the speech intelligibility or communicative participation of children with dysarthria.

Search strategy: 

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2015 , Issue 7 ), MEDLINE, EMBASE, CINAHL , LLBA, ERIC, PsychInfo, Web of Science, Scopus, UK National Research Register and Dissertation Abstracts up to July 2015, handsearched relevant journals published between 1980 and July 2015, and searched proceedings of relevant conferences between 1996 to 2015. We placed no restrictions on the language or setting of the studies. A previous version of this review considered studies published up to April 2009. In this update we searched for studies published from April 2009 to July 2015.

Selection criteria: 

We considered randomised controlled trials and studies using quasi-experimental designs in which children were allocated to groups using non-random methods.

Data collection and analysis: 

One author (LP) conducted searches of all databases, journals and conference reports. All searches included a reliability check in which a second review author independently checked a random sample comprising 15% of all identified reports. We planned that two review authors would independently assess the quality and extract data from eligible studies.

Main results: 

No randomised controlled trials or group studies were identified.