Table 2 Segmental and global inter-study reproducibility for five different feature tracking strain parameters and the study sample size required to detect an absolute change of 5% with 90% power and an α error of 0.05

−3.5 ± 7.5%

35.9%

0.57 (0.35-0.71)

48

1.2 ± 6.5%

38.0%

0.68 (0.55-0.78)

36

1.5 ± 9.2%

53.2%

0.62 (0.47-0.73)

72

−1.0 ± 11.3

55.4%

0.59 (0.44-0.71)

108

−1.9 ± 13.6

60.0%

0.56 (0.41-0.69)

156

−3.2 ± 5.7%

27.2%

0.61 (0.15-0.85)

28

1.0 ± 3.5%

20.3%

0.70 (0.32-0.89)

11

1.5 ± 5.8%

33.3%

0.44 (0–0.77)

29

−1.08 ± 5.4%

26.4%

0.44 (0–0.77)

25

−1.9 ± 6.8%

29.9%

0.62 (0.20-0.85)

39