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Sheffield investigators

Rebecca Palmer

Cindy Cooper

Pam Enderby

Steven Julious

Nick Latimer

Sheffield researchers

Liz Cross

Madeleine Harrison

Ellen Bradley

Helen Witts


Glasgow Caledonian University

University of Manchester


National Institute for Health Research (NIHR) Health Technology Assessment (HTA) programme with additional support from the Tavistock Trust for Aphasia

About the project

Clinical and cost effectiveness of aphasia computer therapy compared with usual stimulation or attention control long-term post stroke (Big CACTUS).

Aphasia is a communication disorder often caused by stroke. It affects the ability to understand, talk, read and write. People with aphasia rarely receive treatment from NHS speech and language therapists for more than three months. It has been established that people with aphasia can continue to improve their communication with prolonged treatment (beyond 12 months), but this is rarely available.

StepByStep was a computer program designed to help people practice exercises to improve their ability to find the correct words when they were talking. Following a successful pilot study (CACTUS), Big CACTUS' aim was to compare computer therapy with attention control (puzzle books) and usual care to see if the use of computer software with assistance from a volunteer/speech therapy assistant could improve the ability of people with aphasia to talk.

The research established whether people with aphasia could continue to improve their ability to talk after completion of traditional NHS therapy, and whether this could be cost effective by offering computer treatment at home. Benefits to patients included the opportunity for continued treatment and thus improved ability to talk. It also gave patients independence and control over their therapy. The NHS benefited by being able to support a long-term aphasia treatment service without increasing demand on therapy resources.

A total of 278 participants were recruited to the trial from 20 UK centres between October 2014 and August 2016. The participants were followed up for 12 months and the results found that self-managed computer therapy tailored by a speech and language therapist and supported by speech and language therapy assistants or volunteers increased the amount of speech and language therapy provided.

People with aphasia improved their ability to find words with the addition of computer therapy. These improvements lasted for at least six months after the therapy had ended (therapy may have only lasted for six months but participants could continue to use the computer for longer). People with aphasia made improvements at any time post stroke, it did not matter how long ago the stroke happened.

Most people with aphasia did not automatically use newly learned words in conversation however, one third of people with aphasia did use more words in conversation and more practice of the words may be needed in everyday contexts. People with aphasia did not indicate significant improvements in their everyday communication or quality of life on a rating scale but carers did notice small improvements in their communication skills. The addition of this specific computer therapy approach was unlikely to be cost effective for everyone with word finding difficulties.

The computer therapy approach was most likely to be cost effective for those with mild and moderate word finding difficulties. The computer approach to delivering more word finding therapy in the longer term post stroke was relatively inexpensive and it was half the cost of delivering the same amount of additional therapy face-to-face by a speech and language therapist.

People with aphasia can improve their word finding with extra practice provided at low cost by a computer therapy approach. This could be a useful addition to speech and language therapy services and it is important to encourage the use of new words in everyday communication to improve the overall quality of life.

A full report is in the form of a monograph published in the NIHR HTA journals library and the results of the big CACTUS project have been published in the The Lancet Neurology.

Visit the Big CACTUS web pages for more information including study protocol and a therapy manual. The results of the study, a booklet and video are also available there.

Big CACTUS Twitter


The trial is being measured over time and Big CACTUS has been used as an impact case study for the NIHR. To date, impact includes:

  • Recommendation of the self-managed computer therapy approach to practicing repetitive language exercises in the International Stroke Rehabilitation Guidelines published by Springer.

  • Improvements to the StepbyStep software available to clinicians and patients.

  • Use of the words identified as most meaningful to people with aphasia in three commercial aphasia software programmes.

  • Greater use of computer software to provide increased therapy dose in trial sites.

  • Adoption of the self-managed therapy approach to deliver services during the COVID-19 pandemic.

  • Changes in the practice of therapists to use software for repetitive self-managed practice and augment this with face-to-face therapy to promote new skills (reported by a therapist who had been involved in the trial).