Table 4.

Blood-based chemistry testing (LabCorp).

Testa	Construct assessed and/or rationale	Consent visit: eligibility screening	Assessment: baseline	Assessments: 3 and 6 months
Glycosylated hemoglobin	Inclusionary test and study variable: level of overall glucose control	✓	✓	✓
C-peptide	Inclusionary testb: confirms type 2 diabetes among individuals using exogenous insulin	✓	—	—
Thyroid stimulating hormone	Exclusionary test: rules out an untreated thyroid disorder	✓	—	—
Comprehensive metabolic panel	Exclusionary test: rules out liver and/or kidney dysfunction; study variable: liver enzymes	✓	✓	✓
Glucose, plasma	Study variable: allows for calculation of insulin resistance and fasting glucose	—	✓	✓
Insulin, plasma	Study variable: allows for calculation of insulin resistance and fasting glucose	—	✓	✓
High-sensitivity C-reactive protein	Study variable: biomarker of inflammation	—	✓	✓
NMR LipoProfile	Study variables: triglycerides and detailed cholesterol measures	—	✓	✓

^aAll samples are collected from individuals in a fasting state.

^bWe assess C-peptide only among potential participants reporting insulin use or a history of diabetic ketoacidosis.