Implications of different DCCT‐aligned HbA_1c methods on GMS clinical indicators

Abstract

DCCT-alignment has improved the transferability of HbA(1c) values; however, it is not perfect. It is important that the limitations of current DCCT-aligned HbA(1c) methods are understood by health-care professionals and policy makers, as these may have important financial and clinical implications.

Point-of-Care Measurements of HbA1c: Simplicity Does Not Mean Laxity With Controls

“…This real-life analysis differed from bench tests, which are usually performed to validate POC-A1C methods (2). Similar tendencies to an underevaluation of HbA 1c by POC methods have been noted already by Holmes et al (3) and by Twomey et al (4) in the context of the U.K. “pay-for-performance program.” At the time of the current study, no sign of a possible drift in HbA 1c determination was given by external quality-control procedures. One cannot minimize the clinical relevance of this transitory drift observed with the POC-A1C device.…”

Different DCCT-aligned HbA1c methods and the GMS contract

“…It is widely assumed that DCCT‐aligned methods would not result in financial differences. Previously, we showed a larger difference compared with this study between a different analyser pairing (the Variant II and the DCA 2000 ® + analyzer, Tarrytown, NY, USA) with a different population (secondary care diabetes centre setting) (9). This difference was both statistically and financially significant for the DM7 and DM8 GMS targets.…”

“…The specimens in this study were specimens that would normally be analysed in this laboratory. As specimens from our diabetes centre are measured at the point of care, the population in this study excluded patients from our diabetes centre and thus the population studies is more representative of primary care practice than our previous study (9). This is important as the distribution of the population studied can have an important bearing on whether any classification differences are statistically significant or not (10,11).…”

Fasting plasma glucose and HbA1c as risk factors for Type 2 diabetes

“…Thus, we consider the impact of the variability of HbA 1c on the results of this study is marginal. Finally, although the JDS and NGSP methods have been reported to be related by a simple addition/subtraction procedure (JDS value + 0.3% = NGSP value) [23,24], there may still be differences in HbA 1c values in different analytical platforms [28,29]. Thus, cut‐off points of HbA 1c when other assay methods are employed may be different from the cut‐off used in this study.…”