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Table 3 Time to Peak Standard Deviation inter- and intra-observer reproducibility

From: Speckle tracking echocardiographically-based analysis of ventricular strain in children: an intervendor comparison

Measurements (n = 15)Mean difference ± SDICC (95% CI)Mean absolute difference ± SD% error Median (IQR)
Inter-observer
 QLAB 10.5
  AP4− 0.5 ± 16.00.62 (0.16, 0.85)11.69 ± 10.4462.71 (11.34–159.25)
  SAXM2.0 ± 17.90.83 (0.56, 0.94)11.49 ± 13.5835.72 (23.53–137.50)
QLAB 10.8-Low
  AP48.4 ± 28.60.67 (0.28, 0.87)21.37 ± 20.1324.47 (14.89–44.58)
  SAXM5.8 ± 20.00.86 (0.64, 0.95)11.36 ± 17.2917.72 (2.63–42.43)
QLAB 10.8-Med
  AP41.7 ± 33.90.35 (− 0.21, 0.73)21.21 ± 25.8817.09 (7.04–56.85)
  SAXM5.7 ± 27.80.74 (0.39, 0.90)13.59 ± 24.7010.28 (2.22–77.84)
QLAB 10.8-High
  AP43.0 ± 24.80.53 (0.04, 0.82)20.26 ± 13.5279.66 (24.51–98.46)
  SAXM−9.3 ± 19.70.81 (0.52, 0.93)10.90 ± 18.7637.79 (10.20–58.59)
TomTec-LFR
  AP4−4.3 ± 37.10.83 (0.56, 0.94)24.02 ± 27.9536.96 (19.78–60.82)
  SAXM6.4 ± 11.90.96 (0.87, 0.99)7.33 ± 11.308.37 (1.58–30.17)
TomTec-HFR
  AP48.5 ± 32.70.81 (0.53, 0.93)18.78 ± 27.7222.71 (7.60–41.19)
  SAXM9.4 ± 16.80.90 (0.69, 0.97)13.87 ± 13.1218.85 (4.86–49.68)
Intra-observer
QLAB 10.5
  AP41.2 ± 10.00.79 (0.47, 0.92)5.75 ± 8.0920.69 (6.26–83.64)
  SAXM0.2 ± 10.00.73 (0.35, 0.90)4.60 ± 8.4130.77 (8.13–93.33)
QLAB 10.8-Low
  AP4− 1.3 ± 39.40.40 (− 0.15, 0.75)20.78 ± 33.0110.30 (5.03–32.49)
  SAXM− 0.8 ± 13.60.80 (0.51, 0.93)7.24 ± 11.3316.34 (4.88–37.40)
QLAB 10.8-Med
  AP4−1.8 ± 35.80.26 (− 0.31, 0.68)18.40 ± 30.4213.81 (5.50–48.81)
  SAXM−14.8 ± 54.60.18 (− 0.34, 0.62)18.71 ± 53.2819.20 (7.00–38.07)
QLAB 10.8-High
  AP44.5 ± 13.60.55 (0.10, 0.81)7.89 ± 11.8723.34 (11.04–59.10)
  SAXM− 0.7 ± 15.40.50 (− 0.02, 0.80)6.75 ± 13.7025.35 (7.13–50.00)
TomTec-LFR
  AP4−13.5 ± 37.70.27 (− 0.22, 0.67)25.59 ± 30.1938.59 (14.49–106.81)
  SAXM4.6 ± 19.20.62 (0.19, 0.85)11.01 ± 16.1714.11 (2.22–33.61)
TomTec-HFR
  AP45.2 ± 19.40.57 (0.11, 0.83)9.87 ± 17.3216.28 (4.98–21.38)
  SAXM1.6 ± 7.30.93 (0.81, 0.98)6.24 ± 3.7123.19 (9.00–30.35)
  1. Time to Peak Standard Deviation parameters are expressed as milliseconds. % error represents the absolute difference|[Reader 2 − Reader1]|/[median of Reader 1 and Reader 2] × 100
  2. Abbreviations: AP4 Apical four-chamber view; CI confidence interval; ICC inter class correlation; IQR interquartile range; QLAB 10.8 Low low quantification smoothness setting; QLAB 10.8 High High quantification smoothness setting; QLAB 10.8 Med medium quantification smoothness setting; SAXM short axis mid papillary muscle level; SD Standard Deviation; TT-30 TomTec at 30 frames per second; TT-H TomTec at high frame rate