Current status of liver function tests in Japan.

Inter-laboratory variations in data obtained from surveillance in Japan were studied. The items evaluated were related to liver function and were as follows: total bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase (gamma-GT), cholinesterase (CHE), lactate dehydrogenase (LD), alkaline phosphatase (ALP) and hepatitis markers. Inter-laboratory coefficients of variations for bilirubin, AST and ALT were acceptable, being less than 10%. but higher variations were found for thle other enzyme assays. Detection of hepatitis markers was acceptable. However. even for parameters with lower inter-laboratory variation, differences in obtained values among different reagents or methods still existed. Thus, standardization will be needed for laboratory data in Japan, and this will contribute to international standardization in laboratory medicine in the future.