TL glow curves were computer simulated for Randall-Wilkins, Garlick-Gibson, May-Patridge and Adirovitch models in a range of activation energies (0.1 to 2.0 eV) which were afterwards recovered by the initial rise method. The systematic error of the recovered energies is always the same independent of the energy used in the simulated curves. It was found that there is no dependence of the error onto the heating rate and there is a dependence of error curves on the models used in computer simulated TL emission. A correction factor can be plotted against the percentage of the peak maxima used in the initial rise for each model and we could apply it even if more than 50% of the ascending part of the glow peak has to be considered.