1. A method for simulating an integrated circuit (IC) design in a circuit design simulator, the method comprising: receiving data representing a circuit design, said data configured for input to and processing by said circuit design simulator; when simulating said circuit design, accessing an integrated circuit quiescent current (IDDQ) prediction macro to model leakage current prediction for said circuit design, said leakage current prediction determinable at a single device, cell, circuit, or IC chip level of said design, specifying in said IDDQ prediction macro an uplift switch value corresponding to one of: said device, cell, circuit, or IC chip level of design being simulated; automatically calculating one or more uplift factors used in said leakage current prediction at one of said single device, cell, circuit, or IC chip level of design based on said switch value, said uplift factor(s) calculated based on device variations effects and implemented in said leakage current prediction model to simulate the leakage current calculations according to the level of design, wherein an uplift factor is a function of a statistical quantity σ lopoly of the polysilicon gate length variation of a transistor, a statistical quantity σ vtsat of the transistor saturation threshold voltage variation, and a statistical quantity σ subx of the transistor sub-threshold slope, wherein for a specified uplift factor switch value modeling a transistor device, σ lopoly =0, σ vtsat is calculated as a function of a statistical quantity σ VthRDF defining a 1-sigma Random-Dopant-Fluctuation Induced Vth Variation and as a function of a number of gate fingers of the modeled transistor device, and σ subx is calculated as a function of a statistical quantity σ subVth defining a 1-sigma subVth Slope Variation and the number of gate fingers of the transistor device being modeled, where Vth is the threshold voltage of the transistor device, wherein a processor device performs at least one of said receiving, accessing, modeling and uplift factor calculating.