Comparison of Population-Based Reference Intervals and Reference Change Values of Some Analytes Used to Diagnose Insulin Resistance
Fatma Nesrin Turan1, Hakan Erbas2, Mustafa Sukru Senocak3, Suphi Vehid41Department of Biostatistics and Informatics Trakya University, Faculty of Medicine, Edirne, Turkey, 2Department of Biochemistry Trakya University, Faculty of Medicine, Edirne, Turkey, 3Department of Biostatistics, Faculty of Medicine, İstanbul University, Istanbul, Turkey, 4Department of Public Health, Faculty of Medicine, İstanbul University, Istanbul, Turkey
Objectives: The aim of this study was to examine the reference change value defined as a normal difference in serial test results to investigate clinically significant changes in a given proportion of all healthy persons. Methods: In all, 18 volunteers were included in a cross-sectional and methodological study. The participants provided 5-mL blood samples twice a day, before and after having breakfast, 3 times in 15-day periods. The levels of glycose and insulin were evaluated biochemically and with a hormone auto-analyzer. Biological variation, the reference change value, and the individual index were calculated. Results: The mean participant age±SD was 40.1±7.81 years, and the median age was 41.0 years (min: 27, max: 55 years). Twelve (66.67%) were female and 6 (33.33%) were male. While fasting blood sugar (FBS) was influenced by both time and individual characteristics (p=0.030 and 0.006, respectively), fasting insulin resistance (FIR) changed over time, but was not influenced by individual characteristics, according to the LOG10 base (p=0.796 and p=0.015, respectively). The level 1 FBS intra-individual variation was 7.62 and the inter-individual variation was 7.69. For level 2, the intra-individual variation was 7.71 and the inter-individual variation was 7.65. The intra-individual variation < the inter-individual variation for FIR in both level 1 (15.50<18.44) and level 2 (15.69<18.37). Conclusion: Measurements of glucose and insulin levels should be examined using the analytic variation values of the device. This study demonstrates the importance of analytical variation, intra- and inter-individual variation, the index of individuality, and reference change value.
Cite This Article
Turan F, Erbas H, Senocak M, Vehid S. Comparison of Population-Based Reference Intervals and Reference Change Values of Some Analytes Used to Diagnose Insulin Resistance. EJMI. 2018; 2(1): 22-28
Corresponding Author: Fatma Nesrin Turan