Center Variation and the Effect of Center and Provider Characteristics on Clinical Outcomes in Kidney Transplantation: A Systematic Review of the Evidence

Background Kidney transplantation is the best treatment option for patients with end-stage renal disease. While patient-level factors affecting survival are established, the presence of variation in the management of transplant recipients remains unknown. Objective The objective of this study was to examine center variation in kidney transplantation and identify center and provider characteristics that may be associated with clinical outcomes. Design This is a systematic review. Data sources Ovid Medline, Embase, and Cochrane library from inception to June 2016 were used. Study eligibility Any study examining the association between center or provider characteristics and graft or patient survival, quality of life, or functional status were included. Results We identified 6327 records and 24 studies met eligibility. Most studies used data registries. Characteristics evaluated include center volume (n = 17), provider volume (n = 2), provider experience (n = 1), center type (n = 2), and location of follow-up (n = 1). Outcomes assessed included graft survival (n = 24) and patient survival (n = 9). Significant center variation was described in 12 of 15 and 5 of 7 studies for graft and patient survival. There was a significant and positive association between center volume and graft and patient survival in 8 and 2 studies, respectively. Provider experience and volume were significantly associated with less allograft loss and provider volume with lower risk of death. There was no association between graft survival and location of follow-up or center type. Limitations There was substantial heterogeneity in the variables assessed and methodology used to analyze associations. Conclusion This systematic review found center variation in kidney transplantation. Future studies in the current era are necessary to better evaluate this important topic.