Guideline for evaluating uncertainty of the long-term stability of JCCLS certified reference standard for enzyme of JSCC method

The Committee on Quality Management of the JSCC (Japan Society of Clinical Chemistry) has now evaluated the expanded uncertainty of JSCC-certified Reference Standard for Enzyme that results from taking long-term stability into consideration as a major influencing factor. The method used to address this issue is similar to that employed by the IRMM (Institute for Reference Materials and Methods). The statistical approach entailed estimating the significance of the slope of the regression line relating catalytic concentration to time on the assumption that an enzyme's catalytic concentration declines linearly with its storage period. This approach was successfully applied to address uncertainty in JSCC CRM-001b and JCCLS CRM-002c. This Committee is announcing the method concretely as a guideline that has been applied on an actual practical basis.