Protocol for the development of a core outcome set for studies of bovine respiratory disease diagnosis in pre-weaned dairy calves

There are many diverse case definitions and diagnostic methods for bovine respiratory disease (BRD) in pre-weaned dairy calves [Background]. Therefore, there exists a need to harmonize methods, criteria, and scales for BRD diagnosis through the development of a core outcome set (COS). The development of a COS for BRD diagnosis in pre-weaned dairy calves will include four steps. The first is a scoping review that is being performed to identify all previously reported BRD case definitions for pre-weaned dairy calves used between and within methods of diagnosis. Second, individual semi-structured interviews with global research experts in BRD in pre-weaned dairy calves will be conducted. Thirdly, using outcomes generated from the first two steps, a two-round Delphi survey involving multiple international stakeholders will be conducted to prioritize outcomes for inclusion in the COS. Finally, a consensus meeting with the global research experts from step two, who also completed step three, will be held to ratify the COS for use in future pre-weaned dairy calf research. Ethical approval will be required for this project. This COS will be disseminated through journal publications, conferences, and presentations. ; Dairy Farmers of Canada