INS and Insulin resistance: However, as indicated by the authors, “The low precision of the estimates from the model (coefficients of variation: 31% for insulin resistance and 32% for beta-cell deficit) limits its use (Matthews et al., 1985).” Most important are, as stated by the authors, the facts that 1° The HOMA model is a model of the glucose-insulin feedback system in the homeostatic (overnight-fasted) state and 2° it has been designed to predict pancreatic β-cell function (%β) and insulin sensitivity (IS) in the fasting steady state.