Aim: Lipid profile is used to determine the risk of cardiovascular diseases (CVD) and to monitor treatment. Reference change value (RCV) represents the clinical significance of the variation between the results of two consecutive tests and laboratory test results exceeding this value are associated with the individuals disease status. In our study, we aimed to calculate the RCV for lipid profile tests such as total cholesterol, triglyceride, HDL-cholesterol and LDL-cholesterol, additionally, to assess the clinical use of the RCV in order to determine to the risk of CVD and monitoring their treatment.

Materials and Methods: The analytic coefficient of variation (CVA) was calculated from internal quality control results. The intra-individual coefficient of variation (CVI) and inter-individual coefficient of variation (CVG) were obtained from Westgards website. For each test, the index of individuality (II) was calculated with the CVI/CVG ratio. To assess tests with index of individuality below 1, percentage of the RCV (RCV%) was used. The RCV% is calculated with the formula z.21/2.[CVA2+CVI2] 1/2.

Results: The RCV% results were calculated as 15% for total cholesterol, 47% for triglyceride, and 19% for HDL-cholesterol and LDL-cholesterol. The II was calculated as 0.388 for total cholesterol, 0.608 for triglyceride, 0.344 for HDL-cholesterol and 0.382 for LDL-cholesterol.

Conclusion: The results for RCV% values identified for lipid profile in the literature are similar to the results obtained in our study. In clinical practice, when the difference between two consecutive lipid profile tests exceed the RCV%, it should be interpreted as a significant change. The RCV% may be used to assess the CVD risk and the efficacy of dyslipidemia treatment.