Objective: However, the analytical and standardization problems have continued, vitamin D status is usually assessed by measuring the plasma concentration of 25-hydroxyvitamin D [25(OH)D]. The aim of this study was to compared vitamin D levels of 50 healthy volunteers measured by High Performance Liquid Chromatography and Immunoassay methods.

Material and Methods: 50 healthy volunteers were involved. Vitamin D was determined both in Agilent 1100 which is used High Performance Liquid Chromatography kits and Roche Diagnostics E170 in plasma specimens. The results were evaluated statistically.

Results: The median value was 16.50 μg/l for High Performance Liquid Chromatography assay and 13.48 μg/l for immunoassay method. A positive correlation was found between methods by Spearman's correlation test (p<0.001, r:0.78). The within-run and between run coefficient of variations for immunoassay method were 3.6 and 3.7 respectively. When we compared the test stabilities of specimens according to the storage condition and time, we found deviations from the initial value.

Conclusion: We conclude that the electrochemiluminescence assay provides the benefits such as improving laboratory workflow and efficiency, being precise, providing greater convenience. We determined that the samples were assayed in the same day.