Hossein Ayatollahi - Department of Biochemistry and Nutrition, School of Medicine, Mashhad University of Medical Sciences and Ghaem Hospital, Mashad
Tayebeh Kianoush - Department of Biochemistry and Nutrition, School of Medicine, Mashhad University of Medical Sciences and Ghaem Hospital, Mashad
Mohammad Khajeh Daluee - Department of Biochemistry and Nutrition, School of Medicine, Mashhad University of Medical Sciences and Ghaem Hospital, Mashad

Background and Objectives: For total analytical error, imprecision (SD) and bias, performance goals for laboratory tests have most often been developed. A total analytical error goal requires that thecombination of errors from all sources (random and systematic errors) be within some acceptable limit.Materials and Methods: Fifty vials of sodium and potassium standards (Sandos Company) were chosen. Then, the concentration of sodium and potassium in these standards were dailymeasured using flame photometry for 50 days at biochemistry laboratory (Ghaem hospital,Mashhad). Thereafter, the mean, standard deviation, random and systematic analytical errors, andtotal analytical error from these values were calculated.Results: The systematic and random analytical errors for standard specimens using flame photometry method for sodium and potassium are με (Na) = 0.36, με (k) = 0.012, σε (Na) = 0.69 andσε (k) = 0.11 respectively. Meanwhile, the total analytical error of flame photometry for measurementof sodium and potassium was 1.74 mM/l and 0.232 mM/l respectively. Conclusion: In this study, it was found out that flame photometry system has good precision and accuracy and its total analytical error for measuring of sodium and potassium are within theacceptable range.

Sodium, Potassium, Flame photometry, Total analytical error