GAD1 and Insulin resistance: To evaluate such differences in the underlying condition in individuals with diabetes, a cluster analysis of six variables (glutamate decarboxylase antibody (GAD-Ab), age at diagnosis, HbA1c, BMI, and homeostatic model assessment 2 estimates of b-cell function and insulin resistance (HOMA2-B and HOMA2-IR)) has recently been conducted, and this identified five clusters with distinct clinical characteristics and outcomes, such as diabetic complications [6].