Ergo4workers: Usability Testing of the First Prototype of an App for the Ergonomic Assessment of Healthcare Professionals

Work-related musculoskeletal disorders (WRMSD) represent a group of inflammatory and degenerative diseases of the locomotor system caused by continuous exposure to risk factors, such as force, posture, and repetition, in the workplace. These disorders are manifested gradually and, over time, symptoms become more persistent. The workers of the healthcare sector are one occupational group facing the severe consequences of WRMSD. Ergonomic risk assessments play a crucial role in monitoring and preventing the occurrence of such disorders. Recent technological advances have enabled direct and reliable exposure measurements with wearable devices. Ergo4workers (E4W) is a system consisting of wearable sensors and a smartphone app whose purpose is to aggregate relevant data from such sensors. It aims to provide an ergonomic assessment of work activities, namely regarding the posture adopted; in the current research applied to healthcare professionals’ work. E4W was developed adopting a User-Centered Design (UCD) approach, in which after an initial phase devoted to the understanding and specifying the context of use, the three following phases are carried out iteratively: specifying user and design requirements; solution design and implementation; and evaluation. This paper describes the usability evaluation of E4W app’s first prototype. Usability tests were performed in a laboratory environment involving seven participants. The Cognitive Walkthrough method was applied, and the participants performed tasks in three different scenarios. Data regarding performance metrics of task success, the time required to perform each task, the number of errors, and actions performed were collected for each scenario. At the end of the test, participants were asked to comment on their interaction with the interface. The performance metrics obtained for each usability test were closely analysed. These results were consistent with the verbal feedback obtained, and improvement opportunities for the prototype were identified. These modifications will be implemented in a second prototype. Overall, the prototype was positively evaluated, as participants mentioned its intuitive functionalities and appealing features, as well as the app’s usefulness.