INS and obesity due to melanocortin 4 receptor deficiency: The index was developed based on the TG, HDL-chol, and BMI in two European cohorts of individuals with obesity8: the β-Cell Function in Juvenile Diabetes and Obesity (Beta JUDO) study cohort (n = 29; mean age 15y), and the Relationship between Insulin Sensitivity and Cardiovascular Disease (RISC) study cohort (n = 1,260; mean age 44y).