Quality control, quality assessment of laboratory tests, lipid profile.

ABSTRACT

The first external quality control survey implemented by the Japan Medical Association was performed in 1967, and now. 2.400 or more laboratories are participating in this survey. The survey for total cholesterol was performed from the first survey, triglyceride survey was started in 1973, and survey of HDL-cholesterol was started in 1981. CVs of results for above items in the surveys were greatly improved after the 1980's. CVs in the 1970's were 8 to 10 per cent. but from the middle of the 1980's they were about 3 per cent or less. The main reason for this improvement is the introduction of automated analyzers in laboratories. An additional reason for this improvement is the requirement for accuracy of cholesterol determination by physicians, because the Japan Society of Atherosclerosis decided the consensus value of cholesterol for the initiation of treatment in 1987. Supply of standard material for cholesterol since 1995 is also a reason for this improvement. In 1995. CVs of cholesterol assays by were less than 3% when using most determination kits. Two determination kits, however, were found to give very high CVs. Both of them used dry chemistry, and the reason for these discrepancies was matrix effects of the survey material.