Assessment of a New Blood Glucose Strip: Comparison of Visidex, Visidex II, and Chemstrip bG with Glucose Analyzer Determination of Blood Glucose

Abstract

Chemical test strips for estimating blood glucose are reliable, rapid, and convenient when properly used. Ames (Miles Laboratories, Elkhart, Indiana) has recently introduced a new product, Visidex II, which does not require water for development. This study compares the Visidex II with its predecessor Visidex, an established test strip, the Bio-Dynamics Chemstrip bG (Boehringer-Mannheim, Indianapolis, Indiana), and plasma glucose as measured by standard laboratory methods. Determination of blood glucose by visual inspection by all chemical test strips gave an estimation of true plasma glucose, and was reliable in predicting those values that were hypo- and hyperglycemic, although Chemstrip bG tended to underestimate in the hypo- and euglycemic ranges. Visidex II is more convenient to use than Visidex and is equally reliable in estimating true plasma glucose. In addition, strips from 20 patient samples were read daily for 7 days. Reacted Chemstrip bG test strips began to deteriorate within 24 h, and showed a 27% decline in estimations by day 3. Reacted Visidex II strips were stable for 1 day, but then rapidly declined to 50% of the original estimation by day 4.

Test Strip Comparison: Visidex and Chemstrip

“…Using the same categories as Canfield et al, 1 we continued to demonstrate greater accuracy with CS, despite remarkably similar overall accuracy for VDII in the two studies (58.9% versus 61.0%)' (Table 1). We found correlation coefficients of 0.95 and 0.93 for CS and 0.87 and 0.88 for VDII.…”

“…A further difference between our own studies and that of Canfield et al 1 is the minimal interpolation that is done by these examiners. If a result falls between two color blocks, it is read as halfway between the two blocks.…”

“…In Figure 2, 1 20 strips from the same 20 specimens are compared for stability, but the CS start at a mean of 120 whereas the VDII start at a mean of 170. 4 In summary, we consider the report by Canfield et al 1 to be seriously flawed and their conclusions unsupportable. There is no indication what the reference mean was for this set of specimens.…”

“…There are serious shortcomings in the design of the report of Canfield et al 1 First, the reference method used was glucose oxidase, whereas the CS is standardized using hexokinase. There are serious shortcomings in the design of the report of Canfield et al 1 First, the reference method used was glucose oxidase, whereas the CS is standardized using hexokinase.…”