Which method is recognized as the gold standard for determining hemoglobin concentration?

The cyanmethemoglobin method is recognized as the gold standard for determining hemoglobin concentration because it provides a reliable and accurate measurement of the hemoglobin levels in blood. This method involves the conversion of hemoglobin to cyanmethemoglobin through a reaction with potassium ferricyanide and potassium cyanide, resulting in a stable compound that can be quantitated spectrophotometrically. It is widely used in laboratory settings due to its high precision and ability to measure a broad range of hemoglobin levels.

The alternative methods may have their advantages in certain contexts, but they often lack the robustness and accuracy that the cyanmethemoglobin method provides. For instance, the Sahli method, while historically significant, is less accurate and more subjective, depending on visual interpretation. The Hemo Cue method, although convenient and used for point-of-care testing, might not be as precise as the cyanmethemoglobin method in controlled laboratory settings. The electrochemical method can offer rapid results, but it often does not match the comprehensive validity established by the standard method. Therefore, the cyanmethemoglobin method's established reliability in clinical practice solidifies its status as the gold standard for hemoglobin concentration determination.