Abstract
Expressing the reliability of measurement results by using uncertainty is becoming the international rule. We have reported on an uncertainty estimation method for the routine test data and assigned values of calibrator by differentiating the calibration procedures for the measurement methods into those that are performed each time and those that are performed at certain intervals. This paper discusses the measurement methods whose calibration curve are not linear and presents the methods for estimating the uncertainty of these measurements by means of examples, including specific procedures. While measurements involving non-linear calibration curve, such as immunochemical analysis methods, have recently been used on an extensive scale the fact remains that the methods of expressing the reliability of the measurement data have not been sufficiently examined. We therefore take this opportunity to present here a method for estimating uncertainty based on repeat measurement values, using as samples the reference materials employed for the preparation of the calibration curve.
