The Relationship between Subjective and Objective Usability Metrics for Home Healthcare Devices

Abstract

Home healthcare devices have gained attention recently as more and more care is being delivered in the patients’ home rather than in a hospital setting. This trend is accelerating as healthcare systems work to restrain costs and provide patients with the tangible benefits of receiving care in their own home. Because the user population of these devices is moving away from trained professionals, the usability of home healthcare devices takes on greater importance. Poor usability of these devices could result in negative consequences, ranging from incorrect diagnoses to patient injury or death. In this study, the usability of four common home healthcare devices (a manual blood pressure monitor, a temporal artery thermometer, a pulse oximeter, and a spirometer) was evaluated by 74 participants. The objective metrics of effectiveness (success), efficiency (time on task) and the subjective metric of satisfaction were collected for each device, and correlated with the users’ subjective assessment of the usability of each device, as measured with the System Usability Scale (SUS). Results show that there is a positive correlation between effectiveness and SUS scores, no correlation between efficiency and SUS, and a positive correlation between satisfaction and SUS.