Method for estimating confidence levels for measurements by blood glucose monitoring systems.
A joint conference on self-monitoring of blood glucose (SMBG) has proposed that all glucose monitoring systems generate values that are within 10% of the actual blood glucose level 100% of the time. To estimate the confidence limits of blood glucose measurements made in a typical university ambulatory care setting and to ascertain whether they met the proposed standard, we performed duplicate determinations of blood glucose using a reflectance meter and applied to the measurements a method for calculating the closeness of measured values to a "true" mean. Based on paired measurements in 100 consecutive diabetic subjects, we were able to show that one measurement would be within 11.9% of a true mean value 95% of the time and within 8.4% of the mean 90% of the time. The 95 and 90% confidence limits for the average of two repeated measurements were calculated to be 8.4 and 5.9%, respectively. Our methodology can be applied to any set of SMBG values to calculate their confidence limits and to determine whether the measurements meet recommended standards.
Kelly
T M
TM
Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City.
Jensen
R L
RL
Robinson
M K
MK
D015190:Blood Glucose Self-Monitoring / Q000379:methods / Q000592:standards*; D003920:Diabetes Mellitus / Q000097:blood*; D006801:Humans; D013223:Statistics as Topic