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Abstract Background Over the years, the measurement of Glycated Hemoglobin (A1c) has solidified as an important risk marker for pre-diabetic patients and for the diagnosis and control of diabetic patients. The High-Performance Liquid Chromatography (CLAE) method has been adopted in prospective studies such as the DDCT, and international certification by the NGSP is available. In this study, analytical performance metrics including imprecision, correlation, linearity, carryover, and detection of hemoglobin variants were evaluated for the Lifotronic® H100 Plus analyzer from China. Methods The results were evaluated following CLSI guidelines on samples within stability, collected according to standardized procedures. For the comparative method, 40 patient samples ranging from 4 to 15.4% were analyzed, and two concentrations of internal quality control material were used for intra-assay (5 repetitions per day) and inter-assay (over five days) imprecision testing. Linearity was assessed using samples at two concentrations, one low (4.5%) and another high (17.2%). For carryover evaluation, low (4.98%), intermediate (9.97%), and high (14.96%) concentrations were assayed in an interleaved manner. Hemoglobin variants found in the studied population were determined using the same method employed in correlation tests (HbS, HbF, HbC, HbE, and HbD). Results The method comparison study revealed a Total Error for decision levels of 5.6%: 2.23% and 6.5%: 1.70%, which were lower than the maximum allowable Total Error of 3.3% (EFLM - EuBIVAS). The difference plot showed that 95% of the results fell within acceptable limits. Positive bias was observed in 7 out of 40 tested samples, predominantly in samples with concentrations above 6,5%, although the medical team assessed it as having no clinical impact. For intra-assay imprecision, the obtained result was 0.86%, and for inter-assay imprecision, it was 0.87%, both deemed acceptable according to the 3.0 % specification proposed by the supplier for the two tested levels.Linearity tests were approved for concentrations proposed by the manufacturer between 3 and 18%, and no carryover was found between samples. All hemoglobin variants previously detected in the comparative method were also identified in the test method without exception, although the specific type of Hb variant was not identified. Conclusions The Lifotronic™ H100Plus analyzer demonstrated approved analytical performance with some notable observations: positive bias was observed in samples with concentrations above 6,5%, though it was not considered clinically relevant, the throughput of 58 tests per hour could be a limitation for laboratories with high testing volumes and the analyzer detected the presence of Hb variants, although it did not identify their specific types.
Canali et al. (Tue,) studied this question.