Study Protocol: Core Outcome Set for cranioplasty following stroke or TBI 'COAST Study' (Preprint)

BACKGROUND Core Outcome sets (COS) are important and necessary as they help standardize reporting in research studies. Cranioplasty following traumatic brain injury or stroke is becoming increasingly common leading to an ever growing clinical and research interest especially regarding the optimal material, cost-effectiveness, and timing of cranioplasty concerning neurological recovery and complications. Consequently, heterogeneous reporting of outcomes from such diverse studies has led to a limited meta-analysis ability, with the ongoing risk of outcome reporting bias. OBJECTIVE To define a standardized COS for reporting in all future TBI and stroke cranioplasty studies. METHODS An international steering committee has been formed to guide the development of the COS. In addition, recommendations from other clinical initiatives such as COMET (Core Outcomes and Effectiveness Trials) and OMERACT (Outcome Measures in Rheumatology) have been adhered to. The first phase of the project is data-collection through a systematic review and qualitative study. The second phase will be the COS-formation through a Delphi survey and consensus meeting. A definition of consensus will be decided and agreed upon before the Delphi survey begins to avoid bias, which is planned for the end of 2021. RESULTS The development of a cranioplasty COS that can be applied in future research, helping to align future studies, building an increased understanding of cranioplasty and its impact on a patients function and recovery. CONCLUSIONS This study should result in consensus on a COS for cranioplasty following TBI or stroke. CLINICALTRIAL The study has been registered on the Core Outcome Measures in Effectiveness Trials (COMET) database for COS development.