ESR was greatly influenced by Hct, which caused ESR to lose its original meaning and accuracy. In order to avoid the interference, an equation relating ESR to Hct was derived as
, here K was defined as the coefficient for the equation which could be easily calculated for every tested subject from ESR and Hct. The increase of K implied losing charge on surface of RBC biophysically and associated with the contents of fibrinogen, IgG and IgA. The method using K to test patients instead of origenal ESR showed the good superriority such as exclusion of interference from Hct and increase of accuracy in clinical investigation. The abnormality of some patients with ischemic stroke or acute myocardial infarction could be detected by K, but they were shown in normal range by ESR.
