title: Usability evaluation of a GUI prototype for a ventilator machine.
abstract: OBJECTIVE
  Information presentation on the monitor screen of ventilator machines affects nurses' response and decision-making during ventilation treatment. The purpose of this study is to evaluate whether a new GUI (graphical user interface) prototype, the so-called circular display prototype can make deviations easy to detect.
  
  
  METHODS
  A numerical display prototype was made and used as a reference display in the evaluation. Six task scenarios that involved parameter changes were selected to simulate a real situation under volume control (VC) mode during ventilation treatment. Usability tests with the two display designs were carried out in a usability laboratory. Twenty medical nursing students participated as test subjects in the usability tests.
  
  
  RESULTS
  The objective results showed that the graphical circular display had an advantage over the numerical display in interpreting parameter changes, but not in reducing the error rates for detecting the number of parameter changes or for forming an overall picture of the patient's situation. Furthermore, the circular display prototype did not improve the detection time.
  
  
  CONCLUSIONS
  Although the majority of the test subjects preferred the graphical circular display, the results implied that several aspects of this prototype should be improved in a future development study.
authors.affiliation: Department of Product and Production Development, Division of Human Factors Engineering, Chalmers University of Technology, SE-412 96 Göteborg, Sweden. yuanhua@hfe.chalmers.se
authors.forename: Yuanhua
authors.initials: Y
authors.lastname: Liu
authors.forename: Anna-Lisa
authors.initials: AL
authors.lastname: Osvalder
mesh_terms: D000328:Adult; D003196:Computer Graphics; D003657:Decision Making; D006801:Humans; D009726:Nurses; D010465:Perception; D012121:Respiration, Artificial / Q000295:instrumentation*; D014584:User-Computer Interface