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This paper presents a variety of outcomes data from 24 experienced users of automatic speech recognition (ASR) as a means of computer access. To assess usage and satisfaction, we conducted an in-person survey interview. For those participants who had a choice of computer input methods, 48% reported using ASR for 25% or less of their computer tasks, while 37% used ASR for more than half of their computer tasks. Users' overall satisfaction with ASR was somewhat above neutral (averaging 63 out of 100), and the most important role for ASR was as a means of reducing upper-limb pain and fatigue. To measure user performance, we asked users to perform a series of word processing and operating system tasks with their ASR systems. For 18 of these users, performance without speech was also measured. The time for nontext tasks was significantly slower with speech (p < 0.05). The average rate for entering text was no different with or without speech. Text entry rate with speech varied widely, from 3 to 32 words per minute, as did recognition accuracy, from 72% to 94%. Users who had the best performance tended to be those who employed the best correction strategies while using ASR. [ABSTRACT FROM AUTHOR]

For more than two decades the assistive technology outcomes literature has featured repeated calls for clinical research to demonstrate the impact of device recommendations, as well as substantial discussion of tools for measuring AT outcomes. Unfortunately, data are still not routinely collected in most AT service delivery settings, which undermines the field. This paper describes a framework for developing a national cloud-based system of AT outcomes measurement that emerged from structured discussions with clinicians, researchers, and manufacturers. Such a system would: (a) allow collection and upload of outcomes data by geographically dispersed researchers, practitioners, and consumers; and (b) enable policymakers, third-party funders, consumers, practitioners, and researchers to retrieve outcomes data for specific disability and/or device groups.

Scanning Wizard software helps scanning users improve the setup of their switch and scanning system. This study evaluated Scanning Wizard's effectiveness and usability. Ten people who use switch scanning and ten practitioners used Scanning Wizard in the initial session. Usability was high, based on survey responses averaging over 4.5 out of 5, and qualitative feedback was very positive. Five switch users were able to complete the multi-week protocol, using settings on their own scanning system that were recommended from the Scanning Wizard session. Using these revised settings, text entry rates improved by an average of 71%, ranging from 29% to 172% improvement. Results suggest that Scanning Wizard is a useful tool for improving the configuration of scanning systems for people who use switch scanning to communicate. Implications for Rehabilitation Some individuals with severe physical impairments use switch scanning for spoken and written communication. Scanning Wizard software helps scanning users improve the setup of their switch and scanning system. This study demonstrated high usability of Scanning Wizard (with 10 switch userpractitioner teams) and increased text entry rate by an average of 71% (for five switch users). Results suggest that Scanning Wizard is a useful tool for improving the configuration of scanning systems for people who use switch scanning to communicate.

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.

This study systematically reviewed the research on assistive technology (AT) access interfaces used for text entry, and conducted a quantitative synthesis of text entry rates (TER) associated with common interfaces. We searched 10 databases and included studies in which: typing speed was reported in words per minute (WPM) or equivalent; 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 TER reported for individuals with physical impairments. Studies also had to report the sample size, and the average and standard deviation for the TER data. Thirty-nine studies met the criteria for quantitative synthesis. Studies involved seven interface types: standard keyboard typing, on-screen keyboard (OSK) with cursor selection, OSK with scanning selection, automatic speech recognition (ASR), Morse code, brain-computer interface (BCI), and other. ASR, standard keyboard, cursor OSK, and scanning OSK had at least four studies and 30 subjects, with TER averaging 15.4, 12.5, 4.2, and 1.7 WPM, respectively. When combined with measurements of a particular client's text entry performance, the TER from this review can be used within an evidence-based decision-making process for selecting control interfaces.

Scanning Wizard software helps scanning users improve the setup of their switch and scanning system. This study is evaluating Scanning Wizard's effectiveness, with nine people who use single-switch scanning participating to date. Text entry rates have improved by an average of 71%, ranging from 29 to 172% improvement.

We developed and evaluated a software tool for the automatic configuration of Windows keyboard settings. The software is intended to accommodate the needs of people with physical impairments, with a goal of improved productivity and comfort during typing. The prototype software, called AutoIDA, monitors user activity during performance of regular computer tasks and recommends the Sticky Keys and key repeat settings to meet the user's specific needs. The evaluation study included fourteen individuals with upper extremity impairments. AutoIDA recommended changes to the default keyboard settings for 10 of the 14 participants. For these individuals, average typing speed was essentially the same whether users typed with the default keyboard settings (5.5 wpm) or the AutoIDA-recommended settings (5.3 wpm). Average typing errors decreased with use of the recommended settings, from 17.6% to 13.3%, but this was not quite statistically significant (p = .10). On an individual basis, four participants appeared to improve their overall typing performance with AutoIDA-recommended settings. For more specific metrics, AutoIDA prevented about 90% of inadvertent key repeats (with a revised algorithm) and increased the efficiency and accuracy of entering modified (shifted) characters. Participants agreed that software like AutoIDA would be useful to them (average rating 4.1, where 5 = strongly agree).

This article describes the development and evaluation of a software tool for the automatic configuration of mice and other pointing devices. The software is intended to accommodate the needs of people with physical impairments, with a goal of improved productivity and comfort during computer use. We successfully built prototype software that monitors user activity during performance of regular computer tasks and recommends appropriate Windows mouse settings to meet the user's specific needs. Twelve individuals with upper extremity impairments participated in an evaluation study. On average, the recommended settings significantly improved pointing performance for this subject group. The effect on trial time, entries, and error-free trials was significant at the 0.05 level. Trial time showed the strongest effect, improving by 29.3% with the settings recommended by our software. These results suggest that our software can successfully determine the appropriate mouse settings for an individual, yielding significant improvements in pointing performance.

Single-switch scanning is a technique used by some individuals for spoken and/or written communication. We developed a method for adjusting the settings in a single-switch scanning interface to increase a user's text entry rate (TER). We evaluated that method with nine individuals who use single-switch scanning to communicate. Text entry rates improved by an average of 120% (p = 0.003). All nine subjects increased their TER by at least 40%, and five of the nine increased their TER by over 100%. At baseline, TER averaged 1.42 words per minute (wpm), ranging from 0.28 to 2.92 wpm. With the revised settings, TER averaged 2.72 wpm and ranged from 1.12 to 6.51 wpm.

Purpose: For individuals with severe motor and communicative disabilities, single switch scanning provides a way to access a computer and communicate. A model was developed that utilizes scanning interface settings, error tendencies, error correction strategies, and the matrix configuration to predict a user's communication rate., Method: Five individuals who use single switch scanning transcribed sentences using an on-screen keyboard configured with the settings from their communication devices. Data from these trials were used as input to a model that predicted TER for the baseline configuration and at least three other system configurations. Participants transcribed text with each of these new configurations and the predicted TER was compared to the actual TER., Results: Results showed that predicted TER was accurate to within 90% on average. The scan rate was also entered into a previously published model which assumes error-free performance. For our model, the average error for each participant was 10.49%, compared to 79.7% for the model assuming error-free performance., Conclusions: Our model of row-column scanning was much more accurate than a model that did not consider the likelihood of an error occurring. There is still room for improvement, however, and the results of the study will lead to additional modifications of the model.

Computer access technology (CAT) allows people who have trouble using a standard computer keyboard, mouse, or monitor to access a computer. CAT is critical for enhancing the educational and vocational opportunities of people with disabilities. Choosing the most appropriate CAT is a collaborative decision-making process involving the consumer, clinician(s), and third party payers. The challenges involved and potential technological solutions are discussed.

Purpose: Software was developed which makes recommendations regarding configuration of a computer pointing device, such as a mouse, to accommodate a person's physical impairment. Specifically, a software agent automatically recommends a setting for the computer's control-display gain based on observations of a user's performance in a target selection task., Method: The software agent makes its recommendations based on available adjustment settings in the existing operating system. The agent was evaluated in studies with 12 participants who have motor impairments., Results: The agent-selected gain was not associated with significant improvements in selection time or error-free performance compared with the operating system's default gain. Across participants and trials, gain did not have a significant effect on selection time except at the lowest gain settings tested. However, two participants did have notable and consistent improvement in selection time and error-free performance using the agent-selected gain; gain across trials had a significant effect on number of target entries and number of submovements; and a post-hoc analysis indicated improved target selection time when varying both target size and control-display gain., Conclusion: These observations provide possible avenues for future work, although the current study indicates that changes to control-display gain, alone, are unlikely to offer improvements in speed or accuracy for the general population of people with motor impairments.

Purpose: We are developing a software system called IDA (Input Device Agent), whose goal is to optimally configure input devices for people with physical impairments. This study assessed IDA's ability to recommend three keyboard parameters in response to measurements of typing performance: repeat rate, repeat delay, and use of StickyKeys., Method: Twelve typists with physical impairments participated. The study employed a repeated measures design. Each participant typed six sentences in each of four keyboard conditions: default settings, IDA-recommended repeat settings, StickyKeys On, and a repeat of default settings., Results: Two participants had significant problems with inadvertent key repeats, when using the default repeat settings. For those two participants, use of the IDA-recommended repeat settings reduced the number of repeated characters by 96% and significantly improved text entry rate and typing accuracy. IDA recommended StickyKeys for six participants, each of whom had at least one problem related to modifying keys without StickyKeys. Use of StickyKeys for these individuals eliminated their modifier-related errors and significantly improved typing speed. IDA did not recommend StickyKeys for the six participants who demonstrated no need for it., Conclusions: The results indicate that IDA can provide useful assistance with repeat settings and StickyKeys.

Performance on automatic speech recognition (ASR) systems for users with physical disabilities varies widely between individuals. The goal of this study was to discover some key factors that account for that variation. Using data from 23 experienced ASR users with physical disabilities, the effect of 20 different independent variables on recognition accuracy and text entry rate with ASR was measured using bivariate and multivariate analyses. The results show that use of appropriate correction strategies had the strongest influence on user performance with ASR. The amount of time the user spent on his or her computer, the user's manual typing speed, and the speed with which the ASR system recognized speech were all positively associated with better performance. The amount or perceived adequacy of ASR training did not have a significant impact on performance for this user group.

Row-column scanning is a very slow method of communication. Options for increasing text entry rate include 1) dynamically changing the configuration of the row-column matrix or 2) using rate-enhancement techniques like word prediction, but evidence suggests that increased cognitive load imposed by these methods on the user can result in little or no improvement in text generation rate. An alternative we are investigating is adapting a system's scan delay during run-time. Our goal is to allow a scanning system to adjust its parameters "on the fly" (as opposed to the current practice of setting parameters during clinical assessments). This paper describes the evolution of a one-switch row-column scanning system that adapts its scan rate based on measurements of user performance. Two experiments have been performed to explore the effects of automatically adapting scan delay on users' text entry rate. Our results indicate that automatic adaptation has the potential to enhance text-entry rate without increasing task complexity.