Objective: Preanalytical variables account for most of laboratory errors and there are many factors that affect and contribute to the results from a patient. In recent years surgeons use intraoperative parathormone (PTH) results to evaluate the efficiency of parathyroidectomy operations. In this study our aim was to compare the PTH results measured with serum separator (SST) and rapid serum tubes (RST).

Material and Methods: 20 subjects participated in this study. We waited 30 minutes for serum tubes and 5 minutes for rapid tubes to ensure complete clot formations. After clot formation, all tubes were centrifuged. Parathormone levels were quantified on Siemens Immulite 2000 XPI analyzer.

Results: The group consisted of 7 males and 13 females. The mean of parathormone levels for tubes were; 58.9 ± 35.6 pg/mL for serum tubes and 54.4 ± 33.6 pg/mL for rapid tubes. There was statistically significant difference between SST and RST results (p = 0.009). There was a positive correlation between rapid and serum tubes (p<0.001, r=0.981).

Conclusion: In recent years studies have shown that rapid serum tubes can be useful for emergency test results because of its shorter clotting time. In this study there were significantly different results between tubes. We think it would be more useful with more subjects.