Validation and reliability study of a ventilator usability assessment tool

Background: Usability is an index to assess a product from the viewpoint of users satisfaction, efficiency and productivity improvement. The main attributes of usability that are derived from the human factors are  and used  in usability design of the interfaces Include: compatibility, consistency, flexibility, minimal action, perceptual limitation, usefulness, learnability, ease of use, minimal memory load, user guidance, satisfaction and errors. The main aim of this study was to assess the usability of interface design tool for a ventilator utilized in the hospitals of Arak city, Iran; and study its validation and reliability. Methods and Materials After constructing the initial questionnaire from the standard sources, specific techniques to determine the validity,  and Cronbach's alpha coefficient were used for the validity and reliability study. The study procedure was: determining the scope and dimensions of the questions, drafting questionnaire, assigning members of the expert panel, study, questionnaire data acquisition  and analysis methods, determining acceptance criteria of the questions and the content validity and reliability index. Results Final tool was a 42-items questionnaire. The content validity index (CVI) of questionnaire was 0.86. The results showed that the total Cronbach's alpha coefficient was 0.89 as an acceptable value for the reliability of questionnaire. Conclusion After the final questionnaire design and the appropriate validity and reliability of it, adopting this tool to assess the usability of breathing apparatus (ventilator) is recommended. With usability assessment of such vital instruments, quality improvement, higher efficiency and productivity as well as errors reduction and good design user interface will be achieved. Keywords: usability, ventilator, evaluation questionnaire, content validity, reliability