Linearity and calibration. A clinical laboratory perspective.

This article discusses the relationship of calibration and linearity using the example of glutaraldehyde assayed by high-performance liquid chromatography. Assuming adequate precision and a lack of interference, the relationship of calibration to a method's linear range becomes all important to achieving quality analytical results. Linearity is an objective description of the relationship between a quantitative method's final answer and true analyte concentration. Calibration brings this relationship into correspondence with calibrator concentration. The reportable range is that range within which a specified method produces results within defined allowable error without resorting to dilution of the specimen. The reportable range assumes a linear relationship between true analyte concentration and analytical results.