Co-producing a multi-stakeholder Core Outcome Set for distal Tibia and Ankle fractures (COSTA): a study protocol.

BACKGROUND: Ankle fracture is a common injury with a strong evidence base focused on effectiveness of treatments. However, there are no reporting guidelines on distal tibia and ankle fractures. This has led to heterogeneity in outcome reporting and consequently, restricted the contribution of evidence syntheses. Over the past decade, core outcome sets have been developed to address this issue and are available for several common fractures, including those of the hip, distal radius, and open tibial fractures. This protocol describes the process to co-produce-with patient partners and other key stakeholders-a multi-stakeholder derived Core Outcome Set for distal Tibia and Ankle fractures (COSTA). The scope of COSTA will be for clinical trials. METHODS: The study will have five-stages which will include the following: (i) systematic reviews of existing qualitative studies and outcome reporting in randomised controlled trial studies to inform a developing list of potential outcome domains; (ii) qualitative interviews (including secondary data) and focus groups with patients and healthcare professionals to explore the impact of ankle fracture and the outcomes that really matter; (iii) generation of meaningful outcome statements with the study team, international advisory group and patient partners; (iv) a multi-round, international e-Delphi study to achieve consensus on the core domain set; and (v) an evidence-based consensus on a core measurement set will be achieved through a structured group consensus meeting, recommending best assessment approaches for each of the domains in the core domain set. DISCUSSION: Development of COSTA will provide internationally endorsed outcome assessment guidance for clinical trials for distal tibia and ankle fractures. This will enhance comparative reviews of interventions, potentially reducing reporting bias and research waste.