Assay validation is the characterization of assay performance that all
ows the significance of the values obtained in an assay to be evaluate
d. Biological assays have several inherent sources of variation and th
is has been used as an excuse for years to explain unexpected or unant
icipated results. However,with careful control of reagents and strictl
y controlled procedures, biological assays can be successfully validat
ed to allow accurate quantitation and interpretation of the results ob
tained. (C) 1998 The International Association of Biological Standardi
zation.