A New, Wireless-enabled Blood Glucose Monitoring System That Links to a Smart Mobile Device: Accuracy and User Performance Evaluation.

BACKGROUND: These studies investigated the accuracy of the new Contour®Next ONE blood glucose monitoring system (BGMS) that is designed to sync with the Contour™ Diabetes app on a smartphone or tablet. METHODS: A laboratory study tested fingertip capillary blood samples from 100 subjects in duplicate using 3 test strip lots, based on ISO 15197:2013 Section 6.3 analytical accuracy standards. A clinical study assessed accuracy per ISO 15197:2013 Section 8 criteria. Subjects with (n = 333) or without (n = 43) diabetes and who had not used the BGMS previously were enrolled. Each subject performed a self-test using the BGMS, which was repeated by a site staff member. Alternate site tests and venipunctures were also performed for analysis. A questionnaire was provided to assess user feedback on ease of use. RESULTS: In the laboratory study, 100% (600/600) of combined results for all 3 test strip lots met ISO 15197:2013 Section 6.3 accuracy criteria. In the clinical study, among subjects with diabetes, 99.4% (327/329) of subject self-test results, 99.7% (331/332) of results obtained by study staff, 97.2% (309/318) of subject palm results, and 100% (330/330) of venous results met ISO 15197:2013 Section 8 accuracy criteria. Moreover, 97.6% (321/329) of subject self-test results were within ±10 mg/dl (±0.6 mmol/L) or ±10% of the YSI reference result. Questionnaire results indicated that most subjects considered the system easy to use. CONCLUSIONS: The BGMS exceeded ISO 15197:2013 accuracy criteria in the laboratory and in a clinical setting.

Fundamental Importance of Reference Glucose Analyzer Accuracy for Evaluating the Performance of Blood Glucose Monitoring Systems (BGMSs).

BACKGROUND: As blood glucose monitoring system (BGMS) accuracy is based on comparison of BGMS and laboratory reference glucose analyzer results, reference instrument accuracy is important to discriminate small differences between BGMS and reference glucose analyzer results. Here, we demonstrate the important role of reference glucose analyzer accuracy in BGMS accuracy evaluations. METHODS: Two clinical studies assessed the performance of a new BGMS, using different reference instrument procedures. BGMS and YSI analyzer results were compared for fingertip blood that was obtained by untrained subjects' self-testing and study staff testing, respectively. YSI analyzer accuracy was monitored using traceable serum controls. RESULTS: In study 1 (N = 136), 94.1% of BGMS results were within International Organization for Standardization (ISO) 15197:2013 accuracy criteria; YSI analyzer serum control results showed a negative bias (-0.64% to -2.48%) at the first site and a positive bias (3.36% to 6.91%) at the other site. In study 2 (N = 329), 97.8% of BGMS results were within accuracy criteria; serum controls showed minimal bias (<0.92%) at both sites. CONCLUSIONS: These findings suggest that the ability to demonstrate that a BGMS meets accuracy guidelines is influenced by reference instrument accuracy.

Accuracy and user performance evaluation of the Contour(®) Next Link 2.4 blood glucose monitoring system.

BACKGROUND: The Contour(®) Next Link 2.4 blood glucose monitoring system (BGMS), which communicates wirelessly exclusively with a Medtronic insulin pump, was assessed in 2 separate studies. METHODS: In the laboratory study (N=100), subject capillary fingertip samples were tested in duplicate using 3 test strip lots; accuracy was assessed based on ISO 15197:2013 section 6.3 accuracy criteria (95% within ±15mg/dl or ±15% of reference for glucose <100 and ≥100mg/dl, respectively). In the clinical trial (N=219), untrained subjects with diabetes tested capillary fingertip and palm blood samples and completed an ease-of-use questionnaire. BGMS and YSI glucose analyzer results were compared based on ISO 15197:2013 section 8 accuracy criteria. RESULTS: In the laboratory study, 100% of results met ISO 15197:2013 section 6.3 accuracy criteria. In the clinical trial, 98.6% of capillary fingertip and 97.2% of palm results from subjects met ISO 15197:2013 section 8 accuracy criteria. By Parkes-Consensus Error Grid analysis, 100% of subject capillary fingertip results were within Zone A. Based on questionnaire results, the majority of subjects found the BGMS easy to use. CONCLUSIONS: The BGMS exceeds ISO 15197:2013 section 6.3 and section 8 accuracy criteria in the laboratory and in the hands of untrained users with diabetes.

Comparative Accuracy of 3 Blood Glucose Monitoring Systems that Communicate with an Insulin Pump.

OBJECTIVE: This study compared the accuracy of the Contour® Next Link blood glucose monitoring system (BGMS) with 2 other BGMSs (OneTouch® UltraLink® and Nova Max Link™), all 3 of which can communicate wirelessly with an insulin pump. METHODS: Study staff tested fingerstick samples from 112 subjects aged ≥18 years with each BGMS. All BGMS results were compared to YSI 2300 STAT Plus™ Glucose Analyzer results from the same sample source. To safely obtain a wide range of glucose values, 3 blood samples were obtained from each subject (1 sample was tested fresh from the fingertip [unmodified], and the other 2 samples were modified to raise or lower the glucose concentration). The primary endpoint evaluated was difference in accuracy among the BGMSs across the entire tested glucose range (34 to 561 mg/dL). Additional comparisons were made of accuracy in the low (≤80 mg/dL) and high (>180 mg/dL) glucose ranges. BGMS accuracy was assessed by mean absolute relative difference (MARD). RESULTS: The Contour® Next Link BGMS had a statistically significantly lower MARD from the reference value than the other BGMSs across the entire tested glucose range, calculated using all samples as well as only unmodified (i.e., natural) samples. In the low and high glucose ranges, the Contour® Next Link also had a statistically significantly lower MARD from the reference value than the other BGMSs. CONCLUSION: As assessed by MARD, the Contour® Next Link BGMS was significantly more accurate than the other BGMSs evaluated, all of which can communicate wirelessly with an insulin pump.

Performance evaluation and labeling comprehension of a new blood glucose monitoring system with integrated information management.

BACKGROUND: This study evaluated performance and product labeling of CONTOUR® USB, a new blood glucose monitoring system (BGMS) with integrated diabetes management software and a universal serial bus (USB) port, in the hands of untrained lay users and health care professionals (HCPs). METHOD: Subjects and HCPs tested subject's finger stick capillary blood in parallel using CONTOUR USB meters; deep finger stick blood was tested on a Yellow Springs Instruments (YSI) glucose analyzer for reference. Duplicate results by both subjects and HCPs were obtained to assess system precision. System accuracy was assessed according to International Organization for Standardization (ISO) 15197:2003 guidelines [within ±15 mg/dl of mean YSI results (samples <75 mg/dl) and ±20% (samples ≥75 mg/dl)]. Clinical accuracy was determined by Parkes error grid analysis. Subject labeling comprehension was assessed by HCP ratings of subject proficiency. Key system features and ease-of-use were evaluated by subject questionnaires. RESULTS: All subjects who completed the study (N = 74) successfully performed blood glucose measurements, connected the meter to a laptop computer, and used key features of the system. The system was accurate; 98.6% (146/148) of subject results and 96.6% (143/148) of HCP results exceeded ISO 15197:2003 criteria. All subject and HCP results were clinically accurate (97.3%; zone A) or associated with benign errors (2.7%; zone B). The majority of subjects rated features of the BGMS as "very good" or "excellent." CONCLUSIONS: CONTOUR USB exceeded ISO 15197:2003 system performance criteria in the hands of untrained lay users. Subjects understood the product labeling, found the system easy to use, and successfully performed blood glucose testing.