Evaluation of the Roche Cobas b 101 Glycosylated Hemoglobin Point-of-Care Analyzer

Abstract

Background Glycosylated hemoglobin (HbA1c) is a biomarker to assess long-term glycemic control in diabetic patients and has recently been recommended for diagnosis of diabetes. An evaluation of the Roche Cobas b 101 point-of-care (POC) HbA1c analyzer was conducted to assess its analytical performance. Methods Precision and accuracy were estimated by analyzing 2 control samples 11 times for the within-run experiment and over 11 days for the between-batch precision. Agreement was correlated to the laboratory method, Tosoh Biosciences G8 HbA1c analyzer (n = 51; range of results, 4.7%–15.1%), and a POC method, the Siemens DCA Vantage Hemoglobin A1c System, using leftover EDTA samples from laboratory analysis (n = 16; range of results, 5.5%–14.2%). Lot-to-lot reproducibility was investigated using 11 patient samples analyzed with 2 different reagent lots. Interference from the presence of hemoglobin variants was also investigated. Results The Cobas b 101 analyzer showed good precision. Within-run and between-batch coefficient of variations were 1.6% and 3.5% for level 1 control (mean value, 5.2%), and for level 2 control (mean, 10.2%), coefficient of variations were 0.3% for within run and 3% for between batch. The analyzer had a good agreement with both Tosoh G8 (r = 1, P < 0.001) and DCA Vantage (r = 0.99, P < 0.001). Comparison of 2 different reagent lots showed good agreement, and a linearity experiment confirmed the system to be linear for values from 4% to 14%. Compared with the Tosoh G8 values, no interference from common hemoglobin variants was found on the Cobas b 101 analyzer. Conclusions The Cobas b 101 is a reliable POC analyzer showing good correlation with the laboratory method and acceptable precision. The equipment is easy to use and will be suitable for HbA1c testing at pediatric and intensive care units and for mobile screening programs of our health system.