Tagged MRI provides a noninvasive way to assess the regional function of the heart. Clinical use of myocardial strain measurements from tagged MRI requires identifying new normative values. As for cardiac motion estimation, a variety of methods for quantifying myocardial deformations have been proposed in the image analysis and medical literature, based on heart geometry and continuum mechanics. This article comparatively reviews existing quantification techniques, and synthesizes their results to establish confidence intervals for the standard deformation parameters.