Pathways to Equitable Access to Kidney Transplantation in Spain: A Transformative Mixed-methods Study Protocol

Introduction. Chronic kidney disease (CKD) affects 10%-15% of the global population and is projected to become the fifth leading cause of years of life lost by 2040. Despite the benefits of kidney transplantation (KT), access remains inequitable. In Spain, which leads the world in KT rates per million population, disparities may persist due to structural, territorial, and professional barriers. This study aims to explore the mechanisms underlying treatment deprivation and inequity in KT access using a mixed-methods approach. Methods and analysis. A transformative mixed-methods design will be implemented in four phases: (1) systematic reviews on instruments assessing treatment deprivation and inequalities in CKD and KT; (2) a multicenter quantitative study and qualitative interviews with professionals and patients; (3) a pre-experimental evaluation of a training program on KT; and (4) triangulation and translation of findings to inform national policy. The protocol adheres to GRAMMS and PRISMA guidelines. Ethics and dissemination. Approved by the Hospital del Mar Research Institute Ethics Committee (ID: XX), the study complies with EU data protection laws. Informed consent will be obtained. Findings will be disseminated via peer-reviewed publications, conferences, social media, and patient forums to support equity-focused strategies in KT.