Usability testing of a respiratory interface using computer screen and facial expressions videos

Computer screen videos (CSVs) and users' facial expressions videos (FEVs) are recommended to evaluate systems performance. However, software combining both methods is often non-accessible in clinical research fields. The Observer-XT software is commonly used for clinical research to assess human behaviours. Thus, this study reports on the combination of CSVs and FEVs, to evaluate a graphical user interface (GUI).