Speech generating devices for children with cerebral palsy

Last update: 8 Aug 2016

Speech generating devices are communication systems that produce a voice for children who have difficulty speaking
It can help children connect with family and friends and participate in their environment
There are many types available, ranging in price and complexity.

Who are these for?

Speech generating devices may be suitable for adults as well as children with cerebral palsy who have the following characteristics:
Type of cerebral palsy : Bilateral cerebral palsy, Diplegia, Hemiplegia, Quadriplegia, Unilateral cerebral palsy

More information about cerebral palsy is contained in the What is CP? section.


Gross Motor Function Classification System (GMFCS) – classifies severity of mobility difficulties of children and adolescents with CP.

Walks without limitations in the home and community, climbs stairs and can run and jump, difficulties with speed and coordination.

Walks with limitations, difficulties with long distances and uneven surfaces, uses a railing for climbing stairs, limited running and jumping.

Walks using a hand-held mobility device such as crutches or walking frame, may use wheeled mobility for long distances.

Usually relies on wheeled mobility with assistance, may use powered mobility, usually needs special seating and assistance with transfers.

Usually transported in a manual wheelchair, requires specialised seating and full assistance for transfers.


Manual Ability Classification System (MACS) – classifies severity of upper limb impairment: how children with cerebral palsy use their hands to handle objects in daily activities in the home, school, and community settings.

MACS Level I
Handles objects easily and successfully.

Handles most objects but with somewhat reduced quality and/or speed of achievement.

Handles objects with difficulty; needs help to prepare and/or modify activities.

Handles a limited selection of easily managed objects in adapted situations.

MACS Level V
Does not handle objects and has severely limited ability to perform even simple actions.

Communication ability : CFCS III, CFCS IV, CFCS V

Communication Function Classification System (CFCS) – classifies severity of everyday communication of people with cerebral palsy.

CFCS Level I
Effective Sender and Receiver with unfamiliar and familiar partners.

Effective but slower paced Sender and/or Receiver with unfamiliar and/or familiar partners.

Effective Sender and Receiver with familiar partners.

Inconsistent Sender and/or Receiver with familiar partners.

CFCS Level V
Seldom effective Sender and Receiver even with familiar partners.

Movement disorder : Ataxia, Athetosis, Dystonia, Hypotonia, Spasticity

More information about movement disorders can be found on our websites.

Intellectual ability : No intellectual disability, Mild intellectual disability, Moderate intellectual disability, Severe intellectual disability

A person’s thinking skills – ability to understand ideas, learn and solve problems. People with intellectual disability have difficulty with intellectual functioning which may influence learning, communication, social and daily living skills. Intellectual disability may be mild to very severe.

Specialist speech pathologists and occupational therapists help children and families to choose the best device and to learn to use it across different environments such as home, school and the community.

Cerebral Palsy Alliance speech pathologists and occupational therapists assist individuals and their families to determine whether a speech generating device is a good option.

Find a Cerebral Palsy Alliance service

Fees will apply for therapists to provide assessment and prescription of speech generating devices. Fees will also apply for set up and programming of devices, and support and education for users and their families to learn to use the device effectively. Fees will depend on the service provider and the number of sessions needed. Check with the provider whether fees will also apply for development of a home program, writing reports or funding applications, and therapist travel.

Speech generating devices range in price from less than AUD100 to upwards of AUD15,000 depending on the complexity of the device and whether other equipment, such as eye-gaze control technology or a mounting system for a wheelchair, is necessary. Funding for the equipment may be available and this involves completing an application for funding.

Ask the therapists if you are eligible for funding to assist with fees and equipment costs. People with a disability living in Australia may be eligible for a health care rebate through Medicare or funding from the National Disability Insurance Scheme.

Getting the right speech generating device takes quite a while. Ample time is necessary to explore and trial the different device options. Once the right system has been chosen, a lot of time is required to learn how to operate, program and use the device.

More about speech generating devices

Speech generating devices produce electronic speech for children with cerebral palsy who have difficulty speaking. Also known as voice output communication aids (VOCAs), they can build upon a child’s existing communication strategies, such as sounds, gestures and facial expressions. To maximise the benefit, it is important that the device suits the child and that family and other caregivers are also confident using it.

Communication is a basic human right and is essential for learning and interacting with others. Children with cerebral palsy should be supported to use the best methods of communication available. Using a speech generating device for a conversation takes longer than having a regular conversation. Communication partners need to take plenty of time to engage in conversations which allow children to communicate their thoughts, needs and fears. Adequate instruction of communication partners (see Communication Partner Training) is critical to effectively using speech generating devices and enabling children to communicate1.

Speech generating devices come in a range of sizes, prices and complexity levels. Options to consider include:

  • Speech method - speech produced through the device may be digitised (recorded) or synthesised (computer generated)
  • Screen - the screen of the device may display a single page of words, letters or symbols (called static display) or may allow the child to access multiple layers of pages (dynamic display)
  • The display can include photos, pictures, symbols, words or letters
  • Size - the devices can be small and easily carried or large, requiring mounting on a wheelchair
  • Capabilities - some of the more complex devices can be used to operate a variety of other technologies including televisions, lights, air-conditioning and computers
  • Access – there are different ways that a device may be accessed. Simpler ways are pointing to the screen or plugging in a joystick or more complex options include switch scanning or eye-gaze control technology.
  • Skills and communication needs of the child
  • Preferences of the child and family
  • Costs involved
  • Available support
  • Places the device will be used
  • Other equipment and technology needed
  • Time it will take to set up the system and get help when needed.
  • A child’s communication partner may include all family members, teachers and teachers’ aides, other people in the child’s social and school environment and, very importantly, other children1. Communication partners will need to learn how to operate and modify the device, and how to use it in conversation in different environments such as home, school and the community1.
  • The device will need regular upgrades. Examples include updates to the vocabulary and simple maintenance to ensure it meets the child’s changing needs
  • Regular communication between the family, therapists, school and other carers is important, so that the technology continues to be useful and effective
  • Other communication options are needed for times when the device is unavailable or an alternative system is more efficient. Examples include communication books with symbols or text, or a simple, non-verbal yes/no system
  • A speech generating device needs to be carefully positioned so that the child can see it clearly and reach it. In some instances, the device may need to be mounted on a wheelchair.


A detailed assessment by an occupational therapist or speech pathologist with knowledge of assistive technology and speech generating devices is necessary to see if a speech generating device is likely to be the right option for an individual. If so, the therapist will recommend a trial of speech generating devices.

The following assessments may be used in evaluating the use of speech generating devices:

Best available research evidence

We searched the medical, allied health and education literature to find research evaluating the outcomes of using speech generating devices for children with cerebral palsy.
The search aimed to find the best available evidence of whether speech generating devices improve communication ability, literacy and social interaction.

Numerous case studies give examples of the successful use of speech generating devices by children with cerebral palsy. These case studies illustrate applications of speech generating devices for children with cerebral palsy, but are considered very low level research. One case study found a speech generating device enhanced the development of early language and literacy of a preschool child with spastic quadriplegia2. Another case study of a high school student with athetoid cerebral palsy found that his expressive communication and social interaction with peers in the school setting improved by using a speech generating device3. A final case study reported that a 3 year old child with cerebral palsy used a speech generating device to increase his ability to communicate his needs and wants, and to communicate with unfamiliar people4.

Research evidence is just one piece of information used to make a decision about whether a speech generating device is right for a person with cerebral palsy. These devices can work very well for some people. The fact that so little research has been completed should not deter people with cerebral palsy, their families, caregivers and health professionals from carefully considering trialling a speech generating device.

Research in the area of speech pathology, technology and communication interventions for children with cerebral palsy is complex to carry out5.

  • Children with cerebral palsy are individuals who differ by type and severity of cerebral palsy, whether they have associated impairments (for example, hearing or intellectual disability), their particular communication disorder, communication partners and communication environments
  • The design, function and range of devices are constantly changing with new developments in technology
  • As there are so many factors involved in customising a speech generating device for users, it is difficult to define a uniform intervention to evaluate
  • The number of users are small, the costs of setting up devices can be high and the need to follow up users for a long period of time to evaluate the effectiveness of devices makes it difficult to conduct research.

Date of literature searches: June 2016

  1. Batorowicz, B., Campbell, F., von Tetzchner, S., King, G., & Missiuna, C. (2014). Social participation of school-aged children who use communication aids: The views of children and parents. AAC: Augmentative & Alternative Communication, 30(3), 237-251. See abstract
  2. Mathisen B, Arthur-Kelly M, Kidd J, Nissen C. Using MINSPEAK: A case study of a preschool child with complex communication needs. Disability and Rehabilitation Assistive Technology. 2009;4(5):376-83. See abstract
  3. Stoner JB, Angell ME, Bailey RL. Implementing augmentative and alternative communication in inclusive educational settings: A case study. AAC: Augmentative & Alternative Communication. 2010;26(2):122-35.
  4. Thomas-Stonell, N., Robertson, B., Oddson, B., & Rosenbaum, P. (2015). Communicative participation changes in pre-school children receiving augmentative and alternative communication intervention. International Journal of Speech and Language Pathology, 1-9. doi: 10.3109/17549507.2015.1060530.
  5. Pennington L, Goldbart J, Marshall J. Speech and language therapy to improve the communication skills of children with cerebral palsy. The Cochrane Database of Systematic Reviews. 2004(2):CD003466.