A core outcome set for the wellbeing of healthcare professionals: an international Delphi consensus study.

Background: Healthcare professionals' (HCPs) wellbeing is under sustained pressure globally, with rising sickness absence, burnout, and attrition undermining patient safety, care quality, and system resilience. Outcome measurement is heterogeneous across studies, limiting comparability and synthesis. We aimed to develop an internationally applicable core outcome set (COS) for HCP wellbeing. Methods: We conducted an international, electronic, modified RAND/UCLA Delphi study. Panel members were recruited internationally between May 7, 2025, and July 26, 2025 through personal invitations, snowball sampling, and professional networks. Candidate constructs were collated from a published scoping review and an additional MEDLINE search on economic determinants, organised within the PERMA+4 framework, and provided with standardised definitions. The Delphi process consisted of three sequential survey rounds conducted electronically. Panellists (physicians, nurses, allied HCPs, and health-workforce researchers) rated construct importance on a 9-point scale. Consensus criteria were: include if ≥85% rated 7-9 and <15% rated 1-3; exclude if <50% rated 7-9; all others progressed. In round 1 (July-Sept 2025), the start set of constructs was rated. In round 2 (Sept-Oct 2025), panellists re-rated constructs with group feedback; in round 3 (Nov 2025-Jan 2026), panellists ranked included constructs and indicated priority constructs by level (individual, team, organisation, system). The final COS was determined by panel ranking and subsequently reviewed and endorsed by the Steering Committee. Findings: From 254 candidate constructs, we refined 137 unique constructs for Delphi rating. 57 (100% of invited) panellists completed round 1, 50 (88%) completed round 2, and 46 (81%) completed round 3. Panellists participated from 20 countries across six continents. Thirty constructs met inclusion criteria in round 1; two additional constructs were added from panellist suggestions. After round 2, 62 constructs remained for prioritisation. Ranking yielded a ten-item COS, led by work-life balance, job satisfaction, and quality of life; other prioritised outcomes included motivation, mental health, meaning at work, income satisfaction, work culture, perceived professional growth, and stress. Interpretation: This international consensus COS contributes to outcome homogeneity by defining a set of outcomes for HCP wellbeing across settings. Its use could enhance comparability, support evidence synthesis, and inform quality improvement, while allowing addition of locally meaningful outcomes. Consistent measurement will require subsequent selection of valid, feasible, and context-appropriate instruments for each outcome. Future work should thus select and validate feasible, context-appropriate measurement instruments for each outcome (a core outcome measurement set) and test their cross-cultural measurement properties. Funding: None.