Cobas integra

Hemoglobin A1c (HbA1c) was measured using a laboratory assay standardized to the Diabetes Control and Complications Trial (reference range, 4%-6%, [20–42 mmol ⁄ mol]). Initial A1c assays were performed with the Tosoh (Tosoh Medics, South San Francisco, CA, USA) followed by the Roche Cobas Integra (Indianapolis, IN). All values obtained with the Tosoh were standardized to the Roche assay. Biomedical data were extracted from participants’ medical records including age, sex, diabetes duration, insulin regimen, and frequency of blood glucose monitoring. Measured height and weight were used to calculate youth BMI z-score and parent BMI. Self-report data was used for three parents with missing measured height and weight. Demographic characteristics were assessed by parent self-report.

Data were collected on the day of regularly scheduled clinical appointments. Teens and parents were interviewed by trained research assistants who collected demographic and diabetes management information. Teens and parents completed the surveys described in Section 2.3. Additional diabetes management information was obtained from electronic medical records. Teens were weighed and measured using an electronic scale and stadiometer, both appropriately calibrated, by trained personnel. Body mass index (BMI) percentiles were calculated using the Centers for Disease Control and Prevention growth charts [19 ]. Teens were categorized by weight status according to BMI percentile: underweight (<5th percentile), normal weight (5th to <85th percentile), overweight (85th to <95th percentile), and obese (≥95th percentile). Blood samples were obtained for measurement of HbA1c (ref. range: 4-6%, Roche Cobas Integra, Roche Diagnostics, Indianapolis, IN).

Serial blood draws from an IV catheter were performed before and 15, 30, 45, 60, 90, and 120 minutes after the start of consumption of each beverage. Laboratory samples were immediately submitted for analyses of plasma glucose (Cobas Integra, Roche Diagnostics, Indianapolis, IN). Samples were centrifuged and stored at −80 C for batched analyses of glucagon (RIA, glucagon double antibody, Diagnostics Products Corporation, Los Angeles, CA), insulin (Access Chemluminescent Immunoassay, Beckman Coulter, Fullerton, CA), and metabolic profiling. Metabolite profiling was carried out as previously described [18 (link)]. Absolute quantification of plasma benzoate and hippurate was determined using external calibration curves prepared via serial dilution of sodium benzoate-d5 and N-benzoyl-d5-glycine (C/D/N Isotopes, Pointe-Claire QC) in pooled human plasma (BioreclamationIVT, Westbury NY). Standard curves consisting of eight concentration points for benzoate-d5 and eleven points for N-benzoyl-d5-glycine were analyzed in triplicate.

Each teen provided blood for hemoglobin A1c (HbA1c) assay as part of routine clinical care, measured by the Roche Cobas Integra (Roche Diagnostics, Indianapolis, IN, Ref. range: 4%–6% [20–42 mmol/mol]).

Data were collected through joint adolescent-parent interview, medical record review, and glucose meter/pump downloads. HbA1c assay was performed as part of routine clinical care (Roche Cobas Integra, reference range 4.0–6.0%). Parents provided demographic data. Adolescents and parents completed the following surveys on tablet computers using REDCap software [22 (link)].