Establishment of long-term monitoring system for blood chemistry data by the national health and nutrition survey in Japan.

AIM We established a monitoring system for the annual follow-up of blood chemistry data obtained by the National Health and Nutrition Survey in Japan. METHODS Blood chemistry testing has been entrusted to SRL Inc. We used two external quality control assurance programs established by the Japan Medical Association (JMA) and by CDC/CRMLN during the previous 8-year period. Ten analytes were measured: total cholesterol, HDL cholesterol, triglycerides, urea nitrogen, uric acid, creatinine, AST (GOT), ALT (GPT), gamma-GT (gamma-GTP), and glucose. Total error (TE) was calculated from accuracy by the JMA program and precision by internal quality control of SRL. The permissible range of TE values was determined to be 50% of the evaluation limit on one side in the evaluation criteria of the College of American Pathologists (CAP). When TE fell within the permissible range, the follow-up of annual changes was considered possible. RESULTS Annual follow-up of blood chemistry data was considered possible for all the analytes except urea nitrogen. Based on this study, new permissible TE ranges are proposed. CONCLUSION We confirmed the functioning of the monitoring system for the annual follow-up of blood chemistry data obtained by the National Health and Nutrition Survey in Japan.