Development of a core outcome set for mechanical ventilation trials

Mixed consensus methods were used to develop this COS. A large, international, online Delphi study was performed followed by 2 consensus webinars with representatives from the Delphi panel, with additional input from a separate patient representative group teleconference. Participants represented 4 main stakeholder groups, patients, clinicians, researchers and industry experts.

The Delphi ran over 3 rounds; Round 1 included 24 outcomes obtained by systematic review. During this round a further 23 outcomes were proposed and added by participants. Numbers of participants completing each round were 200, 178 and 161 respectively.

Participants were randomised after the first round into 3 groups each receiving feedback in different forms to facilitate the nested study investigating the impact of feedback mechanisms on the final outcome of the Delphi. A total of 19 outcomes gained consensus through the Delphi process and were discussed at the consensus webinars and the patient teleconference. The outcomes in the final COS were agreed across all meetings and are mortality, health-related quality of life, duration of mechanical ventilation, reintubation, length of stay and successful extubation.

Agreement has also been reached on how these outcomes should be measured and defined, using a process of systematic review and consensus meetings. The nested randomised study suggested that the method of feedback may impact the voting behaviour of participants and may influence the outcomes that are chosen.