A heuristic-based approach for assessing usability in electric powered wheelchairs: A preliminary investigation

Objective: An important issue related to electric powered wheelchair (EPW) is usability. Recent studies did not use heuristic evaluation and did not consider users’ and developers’ participation in the usability evaluation process of the EPW, especially when it has to be driven using alternative commands. Thus, this study investigates the use of heuristics to evaluate the usability of EPW driven by alternative commands, considering the opinion of users and assistive technology (AT) development professionals.MethodsThe study was carried out with 54 participants: 28 EPW users (Group I) and 26 AT developers (Group II). We built a set of 25 heuristics that affects EPW usability. Participants rated each of the 25 heuristics according to their importance for the usability of EPW using the five-point Likert scale. We used the R Software to perform the Wilcoxon Mann–Whitney test as a statistical comparisons test between Group I and II.ResultsThe results showed a statistically significant difference (p<0.05) between Group I and II in the evaluation of 16 heuristics. We identified an important set of heuristics that could help evaluate and improve the usability of EPW.ConclusionThe findings highlighted the importance of considering users’ and developers’ points of view in developing an EPW and its evaluation criteria. It could help the design of the device match the user's needs and expectations. The set of heuristics in this study can be adapted to evaluate other devices’ usability using the heuristic evaluation approach. (AU)

Objetivo: La usabilidad es una cuestión importante relacionada con las sillas de ruedas eléctricas (SRE). Los estudios recientes no han utilizado evaluaciones heurísticas ni han contemplado la participación de los usuarios y desarrolladores en el proceso de evaluación de dichas sillas, especialmente cuando deben conducirse utilizando comandos alternativos. Por ello, este estudio investiga el uso de la heurística para evaluar la usabilidad de las SRE impulsadas por comandos alternativos, considerando la opinión de los usuarios y los profesionales del desarrollo de la tecnología asistencial (TA).MétodosEl estudio se realizó con 54 participantes: 28 usuarios de SRE (Grupo I) y 26 desarrolladores de TA (Grupo II). Construimos un conjunto de 25 heurísticas que afectan a la usabilidad de las SRE. Los sujetos calificaron cada una de las 25 heurísticas de acuerdo con su importancia para la usabilidad de las SRE utilizando la escala de Likert de cinco puntos. Utilizamos el software R para realizar la prueba de Wilcoxon-Mann-Whitney como prueba de comparación estadística entre los Grupos I y II.ResultadosLos resultados reflejaron una diferencia estadística significativa (p < 0,05) entre los Grupos I y II en la evaluación de las 16 heurísticas. Identificamos un conjunto importante de heurísticas que podrían ayudar a evaluar y mejorar la usabilidad de las SRE.ConclusiónLos hallazgos subrayaron la importancia de estimar los puntos de vista de los usuarios y desarrolladores a la hora de desarrollar una SRE, así como sus criterios de evaluación. Estos podrían contribuir a que el diseño del dispositivo coincidiera con las necesidades y expectativas de los usuarios. El conjunto de heurísticas de este estudio puede adaptarse, para evaluar la usabilidad de otros dispositivos, utilizando el enfoque de evaluación heurística. (AU)

A heuristic-based approach for assessing usability in electric powered wheelchairs: A preliminary investigation.

OBJECTIVE: An important issue related to electric powered wheelchair (EPW) is usability. Recent studies did not use heuristic evaluation and did not consider users' and developers' participation in the usability evaluation process of the EPW, especially when it has to be driven using alternative commands. Thus, this study investigates the use of heuristics to evaluate the usability of EPW driven by alternative commands, considering the opinion of users and assistive technology (AT) development professionals. METHODS: The study was carried out with 54 participants: 28 EPW users (Group I) and 26 AT developers (Group II). We built a set of 25 heuristics that affects EPW usability. Participants rated each of the 25 heuristics according to their importance for the usability of EPW using the five-point Likert scale. We used the R Software to perform the Wilcoxon Mann-Whitney test as a statistical comparisons test between Group I and II. RESULTS: The results showed a statistically significant difference (p<0.05) between Group I and II in the evaluation of 16 heuristics. We identified an important set of heuristics that could help evaluate and improve the usability of EPW. CONCLUSION: The findings highlighted the importance of considering users' and developers' points of view in developing an EPW and its evaluation criteria. It could help the design of the device match the user's needs and expectations. The set of heuristics in this study can be adapted to evaluate other devices' usability using the heuristic evaluation approach.