Establishment of working standard for the measurements of total calcium and total magnesium in serum has been studied. This working standard of prototype was prepared by using normal human serum, and adjusting concentration of calcium, magnesium, sodium, potassium and chloride, and pH to those of human serum by the guideline of Committee on Quality Management of JSCC. The working standard of prototype is sealed in vials and frozen to be stored. The values assigned to this working standard of prototype were determined for total calcium and total magnesium by the NIST reference method using an atomic absorption spectrophotometry. The conformity of this reference material of prototype to patient serum make it possible for clinical laboratories to evaluate the trueness of their automated clinical analyzers for total calcium and total magnesium measurement. In addition, the evaluation of inaccuracy in clinical laboratories can be carried out with ease. Thus the traceability for total calcium and total magnesium measurement will be established with this working standard of prototype.
Four International Societies published the statement that, for the standardization of hemoglobin Alc(HbAlc), analytical results should be presented in the both units of IFCC and NGSP. The Committee of Diabetes Mellitus Indices of JSCC was commented acceptance of this statement. The Committee on Standardization of Laboratory Testing for Diabetes Mellitus of JDS is now under working with a standpoint of acceptance of the two units. The both committees started arrangement of circumstances for the standardization of HbAlc measurement in Japan. Thus, a guideline for reporting IFCC units and JDS units on measurement of HbAlc is needed for a practical purpose of manufacturers and end-users in Japan. In the present guideline, the traceability chain being built up on the IFCC peptide mapping procedure as an anchor method, constitution of matrix reference materials for reference and working standards, master equations for the reporting the IFCC and JDS units and/or the IFCC and NGSP units, the criteria of specification of the master equations, and the control system of the HbAlc measurement in routine measurement procedures will be served. The following studies are still remaining: to assign total Hb and HbAlc concentrations as the certified values, to determine the allowance and control limits of the IFCC units in a routine laboratory, to examine the reference intervals and clinical target values using the IFCC unit, to assess the reference system of HbAlc measurement the IFCC unit, and to educate the laboratory staffs, clinicians, and patients on the IFCC unit in the routine medical care.