Analytical performance verification and reference intervals for HbA2 and HbF in adults using the MINICAP Flex Piercing system at Tuyen Quang Provincial General Hospital

Abstract

Objective: Verification of analytical performance and reference intervals of HbA₂ and HbF in adults using the MINICAP Flex Piercing capillary hemoglobin electrophoresis system at Tuyen Quang Provincial General Hospital in 2026. Subjects and Methods: A combined study was conducted, including a laboratory experimental evaluation following CLSI EP15-A3 and CLSI EP06 guidelines, together with a cross-sectional study involving 40 healthy adults aged 18-60 years to verify reference intervals according to CLSI EP28-A3c. Results: The analytical precision of the system met the predefined acceptance criteria, with repeatability and within-laboratory reproducibility coefficients of variation (CV%) below 2.13% for HbA₂ while the CV% for HbF at the single pathological control level was below 0.62%. The bias of HbA₂ ranged from 1.00 to 2.73%, remaining within the allowable limit (≤2.90%), while the bias of HbF was 1.48%. The verified linear analytical ranges were 2.80-6.55% for HbA2 (R²=0.9983) and 0.00-26.35% for HbF (R²=0.9988). Among the 40 healthy participants, all results (100%) fell within the manufacturer’s proposed reference intervals. Conclusions: The HbA₂ and HbF quantification method on the MINICAP Flex Piercing system demonstrated acceptable analytical performance for routine laboratory use. The verified reference intervals are suitable for the local study population and applicable at Tuyen Quang Provincial General Hospital.