Purpose Randomised clinical trials should ideally use harmonised outcomes that are important to patients and to facilitate meta-analyses and ensuring generalisability. Core outcome sets for specific subsets of ICU patients exist, e.g., respiratory failure, delirium, and COVID-19, but not for ICU patients in general. Accordingly, we aimed to develop a core outcome set for adult general ICU patients.

Methods We developed a core outcome set in Denmark following the Core Outcome Measures in Effectiveness Trials (COMET) Handbook. We used a modified Delphi consensus process with multiple methods design, including literature review, survey, semi-structured interviews, and discussions with initially five Danish research panels, involving adult ICU survivors, family members, clinicians, and researchers. The core outcome set was internationally validated in local panels in 14 countries and revised accordingly.

Results We identified 329 published outcomes, of which 50 were included in the 264 participant Delphi survey. After 82 semi-structured survey participant interviews no additional outcomes were added. The first survey round was completed by 249 (94%) participants, and 202 (82%) contributed to the final third round. The initial core outcome set comprised six core outcomes. International validation involved 217 research panel members and resulted in the final core outcome set of survival, free of life support, free of delirium, out of hospital, health-related quality of life, and cognitive function.

Conclusions We developed and internationally validated a core outcome set with six core outcomes to be used in research, specifically clinical trials involving adult general ICU patients.

The authors have declared no competing interest.

https://onlinelibrary.wiley.com/doi/10.1111/aas.14024

https://osf.io/qugyw

The development of this COS is as part of the Intensive Care Platform Trial (INCEPT) research programme (www.incept.dk), which is funded by grants from Sygeforsikringen danmark, and The Novo Nordisk foundation, and supported by Grosserer Jakob Ehrenreich og Hustru Grete Ehrenreichs Fond, Savvaerksejer Jeppe Juhl og Hustru Ovita Juhls Mindelegat, and Dagmar Marshalls Fond. The funders had no influence on any aspects of this study.

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

All Danish participants in the survey and interviews provided written informed consent either by signature (interviews) or ticking confirmed consent in the survey registration. All data were handled confidentially, and participants could withdraw their consent anytime. The Danish Data Protection Agency and Ethical Committee for the Capital Region waived the need for ethical committee assessment (H-21010116).

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Yes

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All data produced in the present work are contained in the manuscript