Real-world data from Europe and Africa suggest that accuracy of systems for self-monitoring of blood glucose is frequently impaired by low hematocrit

Aims: Certain systems for self-monitoring of blood glucose (SMBG) demonstrate inaccuracy at low and high hematocrit (HCT). Manufacturers define HCT ranges for accurate performance. Our objective was to assess the frequency of HCT values that can lead to clinically relevant errors. Methods: In this cross-sectional study, we collected real-world data representing over 360,000 outpatients from the Netherlands (NL), the Czech Republic (CZ), and South Africa (ZA). These were subsequently stratified by sex and age and compared to commonly specified HCT range limits, reference intervals, and data from 1780 healthy Czech subjects. Results: HCT values were comparably distributed in NL and CZ. Outpatients had a higher dispersion of values than healthy subjects. Low HCT values in Europe were common in age groups with a high prevalence of diabetes. All ZA age groups showed a higher prevalence of low HCT than in Europe. Conclusions: Real-world data indicate that SMBG systems specified to perform only within the frequently used 30–55% HCT range would leave 3% of outpatients in Europe and 18% in South Africa at risk of false SMBG results, with individual age strata being substantially higher. This could affect their diabetes management. Adequate SMBG systems should thus be chosen.