1. Fig 2 Task related processing times of naïve operators (blue) and experienced operators (orange) given for the four anaesthesia ventilators in the order in which tasks were tested. Bars indicate means (sd). n/a, tasks were not applicable in the Primus™ because ventilation starts immediately with confirmation of ventilator settings. Please note that owing to the dependence of the data on assistances only descriptive statistics are shown and that the experienced operators were accustomed to working with the Primus™.
From: Comparative usability of modern anaesthesia ventilators: a human factors study
Br J Anaesth. Published online October 03, doi: /bja/aex226
Br J Anaesth | © The Author Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please

2. Fig 1 Frequencies of assistances claimed from naïve operators (blue) and experienced operators (orange) given for the four anaesthesia ventilators in the order in which the tasks were tested. Filled bars indicate frequencies of first assistances; patterned stacked bars indicate frequencies for additional second assistances; third assistances were never necessary. n/a, tasks were not applicable in the Primus™ because ventilation starts immediately with confirmation of ventilator settings. *P<0.05 regarding at least one post hoc comparison between devices. Please note that descriptive statistics were performed using data from the experienced operators and that the experienced operators were accustomed to working with the Primus™.
From: Comparative usability of modern anaesthesia ventilators: a human factors study
Br J Anaesth. Published online October 03, doi: /bja/aex226
Br J Anaesth | © The Author Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please

3. Fig 3 Heat maps calculated from eye-tracking data recorded in naïve operators executing the following selected tasks: (A) ‘set volume controlled ventilation mode’; (B) ‘set inspiratory-to-expiratory ratio to …’; (C) ‘set end-inspiratory pause to …’; (D) ‘quit alarms’; and (E) ‘show emergency oxygen supply’. Red areas suggest a high number of fixations, followed by yellow and green. Blue rectangles indicate the positions of the targeted elements required for completion of the respective tasks.
From: Comparative usability of modern anaesthesia ventilators: a human factors study
Br J Anaesth. Published online October 03, doi: /bja/aex226
Br J Anaesth | © The Author Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please

4. Fig 4 Scores according to the system usability scale (SUS)¹² evaluated by naïve (blue) and experienced operators (orange) given for the four anaesthesia ventilators. *P<0.05 compared with Flow-i within the group of naïve operators (Friedman test followed by Dunn’s multiple comparison test). Please note that descriptive statistics were performed using data from the experienced operators and that the experienced operators were accustomed to working with the Primus™.
From: Comparative usability of modern anaesthesia ventilators: a human factors study
Br J Anaesth. Published online October 03, doi: /bja/aex226
Br J Anaesth | © The Author Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please