Evaluating the Usability of Three Accessible Smartphone Designs by People With Cerebral Palsy

BACKGROUND AND PURPOSE: Mobile phones play an integral role in the lives of people of all ages, occupations, and abilities. The ability to connect with others, access information, and coordinate services is vital to people’s social connectedness and participation, yet accessibility barriers in smartphone design can limit access to these technologies for people with disabilities. Smartphones designed for people with disabilities exist, but there is limited evidence to support their use in a diverse sample of people with disabilities. Therefore, it is critical to evaluate the usability of devices designed for the disability community. A better understanding of smartphone usability can ensure that people with disabilities are matched with the optimal device that meets their needs and desires to promote participation through a modern-day means. The purpose of this study was to evaluate the usability of three accessible smartphones by people with limited hand function secondary to cerebral palsy (CP). Specifically, we evaluated the three aspects of usability: effectiveness, efficiency, and satisfaction. Because this was an exploratory study, hypotheses regarding user preferences were not developed in advance.

METHOD: This study used a descriptive cross-sectional design. Two participants, one ambulatory and one a wheelchair user, in their mid 30s and 40s who self-identified as a person with CP were recruited via purposive sampling through outreach to community contacts. Both participants had significant motor functional impairment in the upper extremity as indicated by Neuro-QOL scores.

Participants completed an individual 2-hr testing session in which they evaluated the usability of three accessible smartphone designs: (1) Open Sesame (Sesame Enable, Rockville, MD), operated via head movement; (2) Sesame Connect (RAZ Mobility, Tysons Corner, VA), operated via joystick; and (3) standard Android smartphone (Google, Mountain View, CA) with accessibility features. Participants completed standardized tasks of picture taking, texting, and accessing the Internet on each phone while the three components of usability were measured. Effectiveness was measured using the Management of Everyday Technology Assessment, efficiency was measured by task completion time, and satisfaction was measured by the Systems Usability Scale and a semistructured interview.

Given the nature of the data and small sample size, all data were analyzed descriptively using a comparative case study approach and Excel (Microsoft, Redmond, WA). Effectiveness, efficiency, and satisfaction scores were compared within individuals and across devices. Interview responses were analyzed using a question-by-question qualitative descriptive analysis.

RESULTS: Initial data show that participants had differing experiences with each of the smartphones and that no device had overall greater usability over another. The ambulatory participant had greater effectiveness and satisfaction with Sesame Connect, whereas the wheelchair user participant successfully completed tasks only with the standard Android smartphone. Neither participant successfully completed tasks using Open Sesame. Participants reported a need for alternative designs with specialized touchscreens and voice control.

CONCLUSION: Smartphones designed for the general disability community may not be the most usable for people with CP with limited hand function to promote participation. Alternative modes of input such as head control may not be as useful as originally thought. People with CP have a wide spectrum of needs and preferences for smartphones that have not yet been fully addressed. Smartphone developers must work to address the diverse needs of this population by including them in the design process.

IMPACT STATEMENT: Better understanding of the experiences of people with CP using diverse accessible smartphone designs can help occupational therapy practitioners make evidence-based recommendations for these vital technologies for people with CP.

References

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