Evaluation of the Accuracy, Precision, and Agreement of a Glucometer Compared to the Standard Laboratory Test in Diabetic and Non-Diabetic Patients

Aim: This study aimed to evaluate the analytical and clinical accuracy, precision, and agreement of the glucosureSTAR point-of-care (POCT) glucometer against the standard laboratory method in diabetic and non-diabetic patients, following the ISO ۱۵۱۹۷:۲۰۱۳ standards. Methods: A cross-sectional study was conducted on ۵۸۹ participants (۳۹۵ diabetic, ۵۱ prediabetic, ۱۳۶ non-diabetic). Paired blood glucose measurements were taken using the glucosureSTAR glucometer (glucose oxidase method) and a Roche Hitachi ۹۱۷ laboratory analyzer. Analytical accuracy was assessed against ISO ۱۵۱۹۷:۲۰۱۳ criteria (±۱۵ mg/dL for values <۱۰۰ mg/dL, ±۱۵% for values ≥۱۰۰ mg/dL). Clinical accuracy was evaluated using Parkes and Clarke Error Grid Analyses. Agreement was statistically analyzed using Bland-Altman plots, Passing-Bablok regression, and the Concordance Correlation Coefficient (CCC). Precision was tested via the coefficient of variation from ۲۰ repeated measurements on three samples. Diagnostic performance was assessed using ROC curve analysis. Results: The analytical accuracy of the glucometer marginally met the ISO ۱۵۱۹۷:۲۰۱۳ criteria (۹۵.۱% of results within ±۱۵ mg/dL or ±۱۵%). While clinical accuracy was acceptable (۱۰۰% of points in Parkes error grid zones A/B), significant systematic error was observed. The device consistently underestimated blood glucose (mean bias: -۳.۳ mg/dL; ۹۵% LoA: -۳۸.۷ to ۳۲.۱ mg/dL) with poor absolute agreement (CCC=۰.۸۸۶). Precision failed ISO requirements at medium and high concentrations. ROC analysis revealed suboptimal diagnostic performance for detecting diabetes (AUC=۰.۸۱۶; sensitivity=۶۲.۱۸%, specificity=۹۳.۲۶% at >۱۲۴ mg/dL cut-off). Conclusion: In conclusion, while the glucosureSTAR glucometer demonstrated acceptable clinical risk assessment with ۱۰۰% of readings in clinically acceptable error grid zones, it showed significant limitations in analytical performance. The device exhibited systematic underestimation, wide variability, and failed to meet precision requirements at medium and high glucose concentrations. With marginal ISO ۱۵۱۹۷:۲۰۱۳ compliance (۹۵.۱%) and suboptimal diagnostic accuracy (sensitivity: ۶۲.۱۸%), this device is unsuitable for diagnostic purposes or therapy adjustment. It may be used with caution for trend monitoring in known diabetic patients where rapid results are prioritized over absolute accuracy, but cannot replace standard laboratory methods when precise measurement is critical.

کلیدواژه ها:

Blood Glucose Self-Monitoring ، Glucometers ، Point-of-Care Testing ، Diabetes Mellitus ، ISO ۱۵۱۹۷:۲۰۱۳ ، Analytical Accuracy ، Clinical Agreement ، Diagnostic Performance