Objective: To gain consensus on the Outcome Measures in Rheumatology (OMERACT) core domain set for rheumatology trials of shared decision making (SDM) interventions.Methods: The process followed... Show moreObjective: To gain consensus on the Outcome Measures in Rheumatology (OMERACT) core domain set for rheumatology trials of shared decision making (SDM) interventions.Methods: The process followed the OMERACT Filter 2.1 methodology, and used consensus-building methods, with patients involved since the inception. After developing the draft core domain set in previous research, we conducted five steps: (i) improving the draft core domain set; (ii) developing and disseminating whiteboard videos to promote its understanding; (iii) conducting an electronic survey to gather feedback on the draft core domain set; (iv) finalizing the core domain set and developing summaries, a plenary session video and discussion boards to promote its understanding; and (v) conducting virtual workshops with voting to endorse the core domain set.Results: A total of 167 participants from 28 countries answered the survey (62% were patients/caregivers). Most participants rated domains as relevant (81%-95%) and clear (82%-93%). A total of 149 participants (n = 48 patients/caregivers, 101 clinicians/researchers) participated in virtual workshops and voted on the proposed core domain set which received endorsement by 95%. Endorsed domains are: 1-Knowledge of options, their potential benefits and harms; 2-Chosen option aligned with each patient's values and preferences; 3-Confidence in the chosen option; 4-Satisfaction with the decision-making process; 5-Adherence to the chosen option and 6-Potential negative consequences of the SDM intervention.Conclusion: We achieved consensus among an international group of stakeholders on the OMERACT core domain set for rheumatology trials of SDM interventions. Future research will develop the Core Outcome Measurement Set.Clinical significance: Prior to this study, there had been no consensus on the OMERACT core domain set for SDM interventions. The current study shows that the OMERACT core domain set achieved a high level of endorsement by key stakeholders, including patients/caregivers, clinicians and researchers.(c) 2021 Elsevier Inc. All rights reserved. Show less