The Vital Check® self-monitoring blood glucose system complies with ISO 15197 (2013).
The study was carried out in 2022; after a favorable opinion from the ethics committee and authorization from the Ministry of the Pharmaceutical Industry; on 110 type 1 and type 2 diabetic patients; followed at the Diabetology center of the Mustapha Pacha University Hospital in Algiers. Three batches of blood glucose strips manufactured locally in full process were evaluated.
The Vital Check® blood glucose reading system met the accuracy requirements of ISO 15197 (2013) for all three lots evaluated in the hematocrit ranges [38-46%]; [30-55%]; [20-60%] for blood glucose values ranging from 23.2 mg/dl to 520 mg/dl respectively with a concordance of 99.8%; 99.2% and 98.7%. Knowing that the standard requires a concordance ≥ 95% of values ± 15mg/dl for blood sugar values < 100mg/dl and ± 15% for blood sugar values ≥ 100mg/dl
While the clinical performance required by the standard must be ≥ 99% of the values in zones A & B of the Parkes error grid. The Vital Check® blood glucose reading system has demonstrated 100% clinical performance, regardless of the batch and hematocrit range studied.
Particularly during low blood glucose levels in patients with a low hematocrit, the Vital Check® blood glucose reading system has demonstrated consistent estimation of capillary blood glucose values with reference blood glucose values.
It should be noted that several factors can have an impact on the determination of accuracy, even in the context of a clinical trial, namely the quality of the reference automaton, the quality of the training of the laboratory personnel activating during the clinical trial, the time between capillary collection and sample analysis and the temperature and humidity conditions.
About the ISO 15 197 (2013) standard
ISO 15197:2013 specifies requirements for in vitro blood glucose monitoring systems in capillary blood samples, specific verification procedures, and validation of performance by intended users.
ISO 15197:2013 is intended for manufacturers of these systems as well as bodies (regulatory authorities and conformity assessment bodies) responsible for evaluating the performance of these systems.
Stricter accuracy requirements for blood glucose meters, in particular an agreement of ≥ 95% of values ± 15mg/dl for blood glucose values < 100mg/dl and ± 15% for blood glucose values ≥ 100mg/dl as well as clinical performance in the Parkes error grid ≥ 95% of values in zone A or > 99% of values in zones A&B
ISO 15197:2013 introduced the assessment of interfering elements (including hematocrit).
About the Parkes error grid
The Parkes error grid, recently re-evaluated, allows real progress in the study of the reliability of self-monitoring of blood glucose and its clinical consequences.
The criteria requiring conformity of the results to > 95% of the concordant values in zone A or > 99% of the concordant values in zone A & Zone B.
This approach consists of distinguishing zones more finely according to the clinical consequences of the measurement error:
· Zone A: represents clinically precise values generally varying by ± 15% compared to those obtained with the reference method
· Zone B represents benign errors for which the inaccuracy is considered to have no clinical consequences
· Zone C represents errors that prompt patients to take actions that overcorrect to an acceptable value