Differences in Glucose Determinations Obtained from Plasma or Whole Blood

Glucose determinations obtained on the AutoAnalyzer from plasma are consistently higher than those obtained from whole blood. The difference is not absolute but tends to increase as the level of the glucose increases. Since there is a close relationship between plasma and whole blood glucose values obtained from the same samples, it is possible to set critical levels which correspond. Such levels are presented for values used frequently in diabetes screening programs or in the interpretation of the standard 100 gm. oral glucose tolerance test. The relationship of glucose values obtained from whole blood and plasma is sufficiently precise that interpretation of data based on whole blood or based on plasma is equally valid as long as adjustments for differences in levels are made. Data are presented which permit the estimation of equivalent values for levels other than those presented.