Relative Inaccuracy of the A1cNow in Children With Type 1 Diabetes
- Larry Fox, MD1,
- Mariya Dontchev, MPH2,
- Katrina Ruedy, MSPH2,
- Roy Beck, MD, PHD2,
- Craig Kollman, PHD2,
- Laurel Messer, RN3,
- Julie Coffey, MSN4,
- Darrell Wilson, MD5,
- Elizabeth Doyle, MSN6,
- William Tamborlane, MD6,
- Michael Steffes, MD, PHD7 and
- The DirecNet Study Group
- 1Nemours Children’s Clinic, Jacksonville, Florida
- 2Jaeb Center for Health Research, Tampa, Florida
- 3Barbara Davis Center, Denver, Colorado
- 4University of Iowa, Iowa City, Iowa
- 5Stanford University, Stanford, California
- 6Yale University, New Haven, Connecticut
- 7University of Minnesota, Minneapolis, Minnesota
- Address correspondence and reprint requests to Larry Fox, MD c/o DirecNet Coordinating Center, Jaeb Center for Health Research, 15310 Amberly Dr., Suite 350, Tampa, FL 33647. E-mail: direcnet{at}jaeb.org
- DCCT, Diabetes Control and Complications Trial
- DirecNet, Diabetes Research in Children Network
- HPLC, high-performance liquid chromatography
- NGSP, National Glycohemoglobin Standardization Program
The Diabetes Control and Complications Trial (DCCT) confirmed the importance of tight glucose control in limiting the development of microvascular complications and established a standard for measuring A1C levels using high-performance liquid chromatography (HPLC) (1). Several studies demonstrated the benefit of rapid A1C testing in the clinic while face-to-face with the patient/family (2–4). The DCA2000 Analyzer (Bayer, Tarrytown, NY) uses an immunoassay method certified by the National Glycohemoglobin Standardization Program (NGSP) (5). It is frequently used to provide a rapid (6 min) A1C result, enhancing the ability to optimize therapy in a timely fashion. We recently reported that the DCA2000 was highly correlated with an HPLC reference (the DCCT standard) (r = 0.94, P < 0.001), although there was a slight bias with DCA2000 values being, on average, 0.2% higher than laboratory values (6).
The A1cNow (Metrika, Sunnyvale, CA) was developed as a single-use, disposable test for measuring A1C at home. It is small, about the size of a pager, requires one drop of blood, and uses an immunoassay. Results are displayed in ∼8 min. However, there has been only one published study (7) to date assessing …
