Comparative diagnosis of the care flow for patients with proximal femoral fractures from admission to the operating room before and after the implementation of the Lean Six Sigma system. RSD [Internet]. 2024 Nov. 16 [cited 2025 Jun. 28];13(11):e01131146843. Available from: https://ojs34.rsdjournal.org/index.php/rsd/article/view/46843