A1cnow device

Data collection was conducted from June 2009 through February 2010. Participants completed an interviewer-administered, fixed-response questionnaire, and a finger stick blood draw for the HbA1c test using the procedures for the Bayer A1cNow+ device. Results were dichotomized at <7.0% and ≥7.0% [20 (link)]. Data collection was conducted at the home of the participant, unless the participant asked to meet elsewhere. Interviewers outlined the project objectives and obtained written informed consent. An incentive ($10) was offered for completing the interview. Informed consent was collected from all study participants. Personal characteristics consisted of age, gender, ethnicity, educational attainment, marital status, and household income. A federally authorized Institutional Review Board (FWA #00001435) approved all sampling, recruitment, and data collection procedures.

During the baseline data collection visit, weight was measured using a standard protocol, with participants in light indoor clothes without shoes, and determined to the nearest 0.1 kg by a calibrated digital scale. Height was measured to the nearest 0.1 cm using a calibrated, wall-mounted stadiometer. Waist circumference was measured to the nearest 0.5 cm at the midpoint between the lower rib and the iliac crest using a Linen non-stretch tape measure with a tension device to provide a constant tension during measurement. Fasting blood glucose (FBG) was measured from capillary blood using a OneTouch Ultra blood glucose monitoring system (LifeScan, Inc., Milipitas, CA). A1C was measured from capillary blood using an A1CNow+ device (Bayer HealthCare LLC, Sunnyvale, CA), an FDA-approved and National Glycohemoglobin Standardization Program-certified instrument that accurately measures A1C in point-of-care settings [12 (link)]. Scales were recalibrated every 6 months. Blood testing devices were tested for quality control daily and recalibrated quarterly.

FBG and HbA1c were measured from capillary blood via finger stick using point of care devices. Fasting blood glucose was measured with a OneTouch Ultra glucometer (LifeScan Inc., Milpitas, CA). HbA1c was measured using an A1cNow + device (Bayer HealthCare LLC, Sunnyvale, CA). While the American Diabetes Association does not recommend the use of point of care devices for diagnostic purposes [29 (link)], these devices were used for data collection in this pragmatic clinical trial because their results have been strongly correlated with standard laboratory tests (R² = 0.712, p < 0.001).
Height was measured barefoot and recorded to the nearest 0.1 cm using a calibrated wall-mounted stadiometer. Weight was measured following a standard protocol with participants wearing light indoor clothes and barefoot and recorded to the nearest 0.1 kg with a calibrated digital scale. Waist circumference was measured at the midpoint between the lower rib and the iliac crest and recorded to the nearest 0.5 cm with a linen non-stretch tape measure with a tension device.