Participatory design for selection of icons to represent daily activities of living for a vision-based rehabilitation-cum-assistance system for locked-in patients.

Purpose: The majority of rehabilitation systems for locked-in patients are used for therapeutic purposes. However, round-the-clock assistance and support are essential after discharge from hospitals or nursing homes. This inspired us to develop a round-the-clock rehabilitation-cum-assistance system operated by eye gazes of locked-in patients. To do this, we aimed to identify the essential daily activities of living for locked-in patients and represent these activities using the most universally acceptable icons/images on the interface for the rehabilitation-cum-assistance system. Method: Activities were selected from available conventions and literature with advice from a local physiotherapy centre. Simple arithmetic averages and weighted averages of recognition rates for different icons representing different daily activities were calculated as per ISO 3864. Universal acceptability of the icons was compared based on responses from 72 locked-in patients across five different age groups. The final icons or images were then selected. Results: Three icons were categorized as identifiable with overall average recognition rates above 66.7%. Icons with average recognition rates 30-60% were considered to have "medium" recognisability and 21 icons were in this category. The average recognition rates of six icons were below 30% and were not acceptable. An overall recognition efficiency of 91% was achieved for participants from all age groups. Conclusions: The most preferred and unambiguous icons or images representing the essential daily activities of living were identified for use on the interface of our rehabilitation-cum-assistance system for round-the-clock operation.Implications for rehabilitationPerforming some of the daily activities by locked-in patients himself/herself is essential for self-independence as well as measures the level of regular improvement.Assistive technologies have huge potential for application for the purpose, especially the vision-based systems.Present technology is useful for development of a vision-based rehabilitation-cum-assistance system for 24 × 7 assistance for the locked-in patients.A new approach for real-time, user-based field evaluation of icons representing daily activities of living using statistical method of averaging of the recognition rates.