<prompt> The anticoagulant of choice for performing coagulation studies is-EDTAHeparin J K 05Tri sodium citrateDouble oxalate  <response>: I. Calcium chelating agents Ethylene diamine tetraacetic acid EDTA:- RBC count, total leucocyte count, eosinophil count, platelet count. Hemoglobin, HbF estimation, and Hb electrophoresis. Double oxalate mixtures of ammonium oxalate and potassium oxalate:- Since the morphology of the blood cells is not well preserved, it is now replaced by EDTA Sodium citrate solution:- Coagulation studies, ESR by Westergren method, blood bank ACD acid citrate dextrose solution was used and now replaced by citrate phosphate dextrose adenine CPDA Sodium fluoride:- Estimation of blood sugar II. Heparin:- Osmotic fragility test, red cell enzyme studies e.g. G6PD and PK deficiency, electrolyte estimation, aerial blood gas analysis. Ref: RAM DAS NAYAK 2nd Ed. Pg no:336 