Reference ranges for analytes in extravascular body fluids.

Interpreting analytes measured in extravascular body fluids can be problematic as the only suitable literature reference, the Geigy Scientific Tables (1), is almost 20 years old, dating back to the year 1981. It is not always possible to apply the values indicated therein to modern analytical procedures since many of these determinations were developed in the 1940es, 1950es and 1960es and measured with methods that have since lost their significance. We therefore did some extensive literature searches to compile an updated list for the most essential extravascular body fluids. The number of analytes featured in the list has been limited to the most relevant substances. A critical examination of the published data revealed that only 10-20% of the papers could actually be used because of insufficient statistical data, too small number of test subjects, or a lack of plausibility.