Reliability of A1CNow+ in a Pediatric Endocrine Clinical Setting
Abstract Number: 1913-P
Authors: JOANE LESS, HEATHER V. SPEER, FRANCOISE SUTTON, SUSAN F. CLARK, Orange, CA
Results: Immediate feedback of A1C results to patients with diabetes has been shown to decrease A1C levels in those patients. Point-of-care A1C testing provides rapid results, allowing immediate feedback and intervention enabling better disease management. A1CNow+™ (Metrika, a subsidiary of Bayer Healthcare., Sunnyvale, CA), a semi-disposable, CLIA-waived point-of-care A1C test is well suited for physician offices, cleared for OTC patient use, is portable and requires no capital equipment purchase. DCA2000 is available only in the clinical setting. Comparison of four HgA1c methods was performed at a pediatric endocrinology hospital based clinic in Southern California.
A1CNow+ was compared to the DCA2000 (Siemens Diagnostics, Tarrytown, NY), the hospital laboratory A1C utilizing the Colorimetric method and a NGSP-Certified Level II Laboratory (Sunnyvale, CA). Subjects provided assent to the IRB-approved protocol, fingerstick testing was performed for the A1CNow+ and DCA2000 testing. Venous blood was drawn and sent to the hospital laboratory and NGSP laboratory. Results were recorded and data analysis was performed using EXCEL.
Fifty subjects ages 7 to 18 years old were enrolled in the study; 56% were male and 44% female. 80% of the subjects had Type 1 diabetes, 10% had Type 2 diabetes and 10% were non-diabetic. Two subjects had results above the linearity of A1CNow+ (>13.0%) and one had result above the linearity of the DCA2000 (>14.0). These results were not included in all data analyses. Least squares linear regression was performed on the data and are presented in the table below.
|DATA SET||n||95% CI|
|A1CNow+ vs. DCA 2000||48||-0.54 to +1.80||1.05||+0.25||0.94||+0.63|
|A1CNow+ vs. Hospital Lab||48||-0.69 to +1.78||1.08||-0.09||0.93||+0.64|
|A1CNow+ vs. NGSP||48||-0.69 to +1.43||1.11||-0.57||0.95||+0.37|
|DCA2000 vs. Hospital Lab||49||-0.93 to +0.71||0.97||+0.17||0.97||-0.11|
|DCA2000 vs. NGSP||49||-1.01 to +0.45||0.98||-0.13||0.97||-0.28|
|Endo Lab vs. NGSP||50||-0.71 to +0.37||1.00||-0.14||0.99||-0.17|
The A1CNow+ results were biased slightly higher than DCA 2000 and both labs. DCA2000 results were biased slightly lower than A1Cnow+ and both labs. Both methods were accurate within the NGSP requirement of ± 1.0%. For clinical use we found that A1CNow+ and DCA2000 were equivalent in accuracy and equally useful in evaluating self care and planning ongoing therapy for improved diabetes management.