Quality control of SMBG in clinical practice.

We present results of quality control of self-monitored blood glucose (SMBG) performed in diabetes outpatient clinic. The tests included: inspection of glucose meter, blood glucose self-measurement by a patient, glucose measurement by point-of-care analyzer used in a clinic and with the laboratory method. In the study 158 glucose meters were controlled and compared with HemoCue glucose analyzer used in the clinic as the reference. 122 glucose meters readings were also compared with the reference laboratory method. Tested glucose meters included: Accutrend {18}, Glucotrend {59}, Precision QiD {39}, One Touch {26} and Glucocard II {16}. Reference glucose assays were performed using glucose oxidase method on Hitachi 911 analyzer. Glucose concentrations measured by the controlled glucose meters ranged from 36 to 425 mg/dL. The analytical bias of the glucose meters amounted from 2.48% to 8.27%. Correlation coefficient between results obtained by the tested glucose meters and HemoCue analyzer ranged from 0.957 to 0.980 and between glucose meters and laboratory method from 0.955 to 0.985. Passing-Bablok agreement test and Deming regression analysis indicated good concordance of results between all the tested glucose meters and HemoCue analyzer, whereas good agreement with the laboratory method was found for Accutrend, Glucotrend, Precision QiD and One Touch glucose meters. In conclusion, good analytical performance of the employed glucose meters and a bias less than 10% from the reference values were found. Results of this study show the possibility for routine, convenient for the patient quality control of SMBG in an outpatient clinic.