A computer-implemented method is disclosed for characterizing a threaded coupling such as between two tubular members, e.g., casing segments employed in the field of oil and gas recovery. In one embodiment, a virtual model of the coupling is generated, and the virtual model is re-arranged to simulate plastic deformation of at least part of the coupling. The re-arranged model is analyzed to derive a stress/strain distribution of the coupling subject to subsequent loading, and an SAF (stress amplification factor) is determined from the analysis that reflects the effect of cyclic loading of the coupling. The method facilitates a thorough assessment of the performance of the coupling in fatigue.