Biological variation estimates of direct and indirect LDL cholesterol by Friedewald and Martin-Hopkins formulas in healthy individuals​Filiz Alkan Baylan Mehmet Özcan Şerif Ercan Ayşe Ciriz Esin Avcı Müjgan Ercan a Medical Biochemistry Department, Faculty of Medicine, Necmettin Erbakan University, Konya, Turkeyb Department of Medical Biochemistry, Faculty of Medicine, Zonguldak Bülent Ecevit University, Zonguldak, Turkeyc Department of Medical Biochemistry, Lüleburgaz State Hospital, Kırklareli, Turkeyd Public Health Laboratory, Malatya, Turkeye Medical Biochemistry Department, Faculty of Medicine, Pamukkale University, Denizli, Turkeyf Department of Medical Biochemistry, Afyonkarahisar Health Sciences University, Afyonkarahisar, Turkeyon December 25, 2025 at 2:18 am