Wu L, et al. - The present study was conducted to examine the time-event association between perioperative red blood cell (RBC) infusion and deep vein thrombosis (DVT) in patients with femoral and pelvic fractures after adjusting for confounding factors and to provide reference for optimizing DVT risk factors. Between May 2018 and December 2019 , researchers retrospectively analyzed the clinical data of 569 patients with femoral and pelvic fractures who received surgical treatment. After 1:1 propensity score matching of 569 individuals enrolled in this research, 126 individuals were in the transfusion group and the non-transfusion group, respectively. The findings indicate that in patients with femoral and pelvic fractures, perioperative RBC infusion is one of the causes of DVT, and the risk of DVT is positively associated with the amount of RBC infusion.