Cobas modular platform

A team of community health workers was trained to enroll participants and to conduct household questionnaires assessing sociodemographic and behavioral variables. Participants were invited to a clinic visit where standing and sitting height, weight, and waist circumference where measured in triplicate using standardized techniques. Systolic and diastolic blood pressure were also measured in triplicate using an automatic monitor (OMRON HEM-780, Omron Healthcare, Hoffman Estates, IL, USA) previously validated for an adult population [39] (link). In this study, we used the mean of the second and third measurements. Fasting blood samples were obtained using standardized methods and calibrated tools [38] . Total cholesterol, triglycerides, high-density lipoprotein cholesterol (HDL-C), and insulin were measured in serum, whereas fasting glucose was assessed in plasma using an enzymatic colorimetric method (GOD-PAP, Modular P-E/Roche-Cobas, Germany). Triglycerides and HDL-C were measured using a Cobas Modular Platform automated analyzer and reagents supplied by Roche Diagnostics (Basel, Switzerland). All samples were analyzed in a single facility, and, for quality assurance, the quality of assays was checked with regular external standards and internal duplicate assays and monitored by BioRad (Hercules, CA, USA).

Fieldwork activities and procedures of the CRONICAS Cohort Study have been described in detail elsewhere.¹⁵ Trained community health workers applied face-to-face questionnaires. After completing the questionnaire, an appointment for a clinical assessment was arranged to ensure an adequate fasting period, between 8 and 12 hours, where a total of 13.5 mL of blood was drawn. Standing height was measured using standardized techniques. After a 5-minute resting period, blood pressure was measured using an automatic monitor OMRON HEM-780 (OMRON, Tokyo, Japan) validated for adult population.
For laboratory procedures, Cobas Modular Platform automated analyzer and reagents from Roche Diagnostics were used to measure triglycerides, total cholesterol, and HDL-c. Also, LDL-c was measured using this method in participants with triglycerides ≥400 mg/dL. However, if participants had triglycerides below 400 mg/dL, the Friedewald equation was used to calculate LDL-c in mg/dL. Non-HDL-c was also estimated by subtracting HDL-c from total cholesterol. Serum glucose was measured using an enzymatic colorimetric method (GOD-PAP; Modular P-E/Roche-Cobas, Grenzach-Wyhlen, Germany).