Standardisation--the theory and the practice.

In 1926 when Sir Henry Dale prepared the first International Standard for insulin and it was adopted by the League of Nations Health Organization (the forerunner of the World Health Organization), biological standardisation was aimed at harmonising the calibration of therapeutic substances.1 Ever since then, the word “standardisation” has meant different things to different people. For example, it has meant the use of a calibration standard in an analytical method, or it has meant the process of adopting the same procedures or methods in order that comparable (harmonised) patient results are achieved. Nowadays the term “standardisation” encompasses the reference measurement procedures and reference materials (i.e. the reference measurement system) required to achieve greater comparability of patient test values between different clinical assays.2 The establishment of reference systems also requires a reliable transfer of analytical accuracy bases by means of a network of reference laboratories performing the reference methods in well-standardised operating conditions.