Reference Range
Because normal and abnormal ranges depend on the laboratory used, it is important to analyze results according to guidelines established by the laboratory running the sample. For example, according to one laboratory, the following parameters are accepted:
A negative antinuclear ribonucleoprotein (anti-RNP) antibody result is defined as less than 20 U based on enzyme-linked immunoassay (ELISA).
A borderline result is defined as 20-25 U.
A positive result is defined as more than 26 U.