Effect of diagnosis, body site and experience on text entry rate of individuals with physical disabilities: a systematic review.

OBJECTIVE: This study systematically reviewed the research on computer text entry by people with physical disabilities, and conducted a quantitative synthesis of text entry rates associated with individuals' diagnosis, body site used with the interface and their level of experience.

METHOD: We searched 10 databases and included studies in which: typing speed was reported; the access interface was available for public use; and individuals with physical impairments were in the study population. For quantitative synthesis, we used only the text entry rates (TER) reported for individuals with physical impairments; studies also had to report the sample size, and the average and standard deviation for the text entry rates.

RESULTS: Thirty-nine studies involving 248 subjects met the criteria for quantitative synthesis. Cerebral palsy was associated with significantly slower TER, at 5.5 wpm, than muscular dystrophy (12.5 wpm), spina bifida (10.4 wpm), SCI high cervical (10.1 wpm) and SCI low cervical (13.3 wpm). Among the 19 body sites represented, the Fingers bilateral category had the highest average, at 17.72 wpm. Head (2.92 wpm) and Hand (non-typing) (3.95 wpm) were each associated with significantly slower TER than Hands unspecified, Fingers bilateral, Hand with control enhancer, Voice and Mouth. The three levels of experience examined, LowPlus, Medium and High, provided very similar TER.

CONCLUSION: This study contributes external evidence for service providers who provide computer access interventions for individuals with disabilities. The analyzed text entry performances serve as benchmarks to be used as guidelines during interface selection and training. Implications for Rehabilitation The median text entry rate (TER) across the literature for individuals with physical disabilities is 7.0 wpm. TER is affected by a user's diagnosis and the body site used for typing. These TER data can serve as diagnostic norms and benchmarks to be used as guidelines during interface selection and training. We recommend that practitioners measure text entry rate with clients, to place their performance in the context of these results and provide a baseline against which to measure effectiveness of an intervention.