Abstract
The aim of this study is to analyze the usability by nurses of the Knowledge-Based System "Diagnostics care for COVID-19." A convenience sample of 16 nurses was selected, among hospital workers and external experts. The group was divided into three subgroups intentionally to obtain different usability perspectives. Usability was evaluated by the System Usability Scale questionnaire. The participants completed the questionnaire on general usability, data inputs, and information output, after completing a minimum of 12 care plans. The first subgroup used real cases and the "think aloud" technique, the second simulated cases from the same hospital, and the third subgroup performed the external simulation. The highest scores were obtained in data inputs (94.38-97.50); and the lowest, in general usability (90.00-95.00). The subgroup of external experts scored the highest (93.13-95.63), and the first subgroup, which carried out real cases, gave the lowest score (90.00-94.38). The "think aloud" technique found an improvement in including more diagnoses and being able to carry out several plans for one person at the same time. The usability obtained was "excellent" in all subgroups and questionnaires, although the application showed limitations related to its characteristics imposed in the requirements specification.