Table 2.

Summary of sources of variations and intra- and inter-modality inconsistencies

Imaging modality related factors	Quality of the acquisition process
	Spatial and temporal resolution
	Segmentation misalignment between imaging modalities
Software-related factors	Spatial and temporal smoothing
	Size of the search region
	Favouring tracking in a certain myocardial layer
	Computation of Lagrangian or Eulerian strain
	Calculation of global strain values
	Definition of end-diastole and end-systole
Operator-related factors	Definition of regions of interest
	Experience and training