Purpose: The measurement of serum ferritin is used as a reliable and noninvasive method for the monitoring of iron stores. There are many different methods for the ferritin measurement. However, the immunoturbidimetric method that having the less cost and possibility of the simultaneously ferritin measurement with other parameters is more useful than electrochemiluminescent method. Thus, we aimed to compare the results of immunoturbidimetric and electrochemiluminescent method.

Material and Methods: The 109 blood samples were analyzed by immunoturbidimetric and electrochemiluminescent method. The comparison study was performed according to the Clinical Laboratory Standards Institute EP9-A3 protocol. The bias between two methods was evaluated according to acceptable systematic error limit. Diagnostic agreement according to the reference value was analyzed by the Kappa test.

Results: Although a strong positive correlation (r=0.999; p<0.001) was detected between the results of immunoturbidimetric and electrochemiluminescent method, it was found a significant difference between the results of two methods (p<0.001). This difference was within the acceptable limits according to the bias obtained from various sources. The agreement of diagnostic according to reference values was good (Kappa value, 0.62; p<0.001) in women; fair (Kappa value, 0.28; p<0.001) in men.

Conclusions: Although there was analytical agreement between immunoturbidimetric and electrochemiluminescence method, it should be considered that the difference may occur at high ferritin levels. It can increase the degree of diagnostic agreement determining the appropriate reference intervals for laboratory's population instead of reference intervals provided by the manufacturer. So, immunoturbidimetric method which having practical advantages may be preferred instead of electrochemiluminescence method.