Bias in medical biochemistry- what laboratory professionals need to know?

Abstract

In medical laboratories, bias presents quantitative expression of trueness, as analytical performance characteristic that describes systematic errors. Despite bias evaluation is an integral part of basic lessons of laboratory quality management, it is still difficult to achieve adequate bias estimation in routine laboratory practice. There are several principles that could be used to estimate bias, but fundamental for evaluating bias in routine medical laboratories is the availability of a suitable reference materials. Besides, it is important that the measuring method and measuring analytical system are in a stable state, and that they have completed an appropriate validation or verification process. This could be checked routinely by the results of internal and/or external quality control. In addition, information about the uncertainty of the certified reference material is a prerequisite for testing the bias. Significant efforts were made to minimized bias in routine laboratory practice, using reference measurement methods and commutable reference materials. Still, there are some challenges that remain for the laboratory professionals as the end users, due to remaining bias between measurement methods and systems from different and/or the same manufacturers.