Cross-validity of a portable glucose capillary monitors in relation to enzymatic spectrophotometer methods

Resumen

The glucose is an important substrate utilizaded during exercise. Accurate measurement of glucose is vital to obtain trustworthy results. The enzymatic spectrophotometer methods are generally considered the “gold standard” laboratory procedure for measuring of glucose (GEnz), is time consuming, costly, and inappropriate for large scale field testing. Compact and portable glucose monitors (GAccu) are quick and easy methods to assess glucose on large numbers of subjects. So, this study aimed to test the cross-validity of GAccu. The sample was composed of 107 men (aged= 35.4±10.7 years; stature= 168.4±6.9 cm; body mass= 73.4±11.2 kg; %fat= 20.9±8.3% – by dual energy x-ray absorptiometry). Blood for measuring fasting glucose was taken in basilar vein (Genz, Bioplus: Bio-2000) and in ring finger (GAccu: Accu-Chek© Advantage©), after a 12-hour overnight fast. GEnz was used as the criterion for cross-validity. Paired t-test shown differences (p<.0005) between GAccu= 86.9±12.1mg/ dL and GEnz= 94.5±12.0mg/dL. The Pearson linear coefficient was r= 0.36 (p<.0005), contingency coefficient= .288 (p<.05), kappa index= .229 (p<.005), standard error of estimate= 11.27mg/dL exceed the 10 mg/dL adopted as cutoff. The American Diabetes Association suggest that error rate to be <10% at the same blood glucose levels. The fasting glucose of individuals was accurately estimated within ±10 mg/dL for around 50% of the men. The results of this study have demonstrated that the GAccu significantly underestimated fasting glucose. In conclusion, the GAccu cannot be cross-validity to assess fasting glucose.