Impact of the format of user instructions on the handling of a wrist blood pressure monitor

Few studies have focused on procedural documents in the field of home medical devices, although incorrect use and usability problems can have important consequences for the patient's health. In this study, we focused on the procedural learning of a home medical device, a blood pressure monitor. Five formats (unimodal: text, audio, pictures; and multimodal: text/audio with pictures) were tested on 124 novice participants randomly assigned to 5 groups. We judged the quality of the formats on the basis of three metrics: efficiency (i.e., handling errors), effectiveness (i.e., consultation time of the procedure, execution time of the devices) and memorability (i.e., recall task). Results suggest that the audio format was more effective than the other groups but also the least efficient. We consider the audio format to be beneficial for patient safety because this format would oblige participants to use a strategy suited to the situation, namely an atomization of the action corresponding to a segmentation of information less likely to saturate working memory. Results in relation to the other formats did not show a more effective, efficient and memorable format. This lack of difference in user performance is nevertheless important, illustrating the need to adapt each instruction to the context of learning, i.e., according to the users, the environment, the resources and the complexity of the task to be executed.