The impact of users' cognitive function on evaluator perceptions of usability.

To explore the association between the user's cognitive function and usability reported by the evaluator. A cross-sectional study was conducted with a community-based sample. Data about participants' age, sex, education, sleep quantity, subjective memory complaints, and cognitive function were collected. A usability session was conducted to evaluate a digital solution called Brain on Track. Independent linear-regression analyses were used to explore univariable and multivariable associations between evaluator-reported usability assessment and the users' cognitive function, age, sex, education, sleep quantity, and subjective memory complaints. A total of 238 participants entered this study, of which 161 (67.6%) were females and the mean age was 42 (SD 12.9) years old. All variables (age, education, sleep quantity, subjective memory complaints and cognitive function) except sex were significantly associated with evaluator-reported usability in the univariable analysis (p < 0.05). Cognitive function, age, education, and subjective memory complaints remained significant in the multivariable model (F = 38.87, p < 0.001) with an adjusted R2 of 0.391. Cognition scores alone showed an adjusted R of 0.288. This work suggests that cognitive function impacts evaluator reported usability, alongside other users' characteristics and needs to be considered in the usability evaluation.