Thị Thanh Đông, Đỗ et al. 2025. APPLICATION OF SIX SIGMA IN THE EVALUATION AND IMPROVEMENT OF BIOCHEMISTRY TESTING PERFORMANCE AT THONG NHAT HOSPITAL. Journal of Health and Aging - Thong Nhat Hospital. 1, 3 (Jul. 2025), 118–124. DOI:https://doi.org/10.63947/bvtn.v1i3.17.