a method of predicting the lifetime reliability of an integrated circuit device with respect to one or more failure mechanisms includes breaking down the integrated circuit device into structures ; breaking down each structure into elements and devices ; evaluating each device to determine whether the device is vulnerable to the failure mechanisms and eliminating devices determined not to be vulnerable ; estimating , for each determined vulnerable device , the impact of a failure of the device on the functionality of the specific element associated therewith , and classifying the failure into a fatal failure or a non - fatal failure , wherein a fatal failure causes the element employing the given device to fail ; determining , for those devices whose failures are fatal , an effective stress degree and / or time ; determining one or more of a failure rate and a probability of fatal failure for the devices , and aggregating the same across the structures and the failure mechanisms .