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Table 4 Sample sizes

From: Quantification of atrial dynamics using cardiovascular magnetic resonance: inter-study reproducibility

   Left atrium Right atrium
   5 % 10 % 15 % 20 % 5 % 10 % 15 % 20 %
Atrial function Volumetric index (%)         
Reservoir; global EF Total 18 5 2 2 47 12 6 3
Conduit EF Passive 135 34 15 9 162 41 18 11
Booster pump EF Booster 391 98 44 25 317 80 36 20
  Strain (%)         
Reservoir εs 27 7 4 2 231 58 26 15
Conduit εe 57 15 7 4 359 90 40 23
Booster pump εa 281 71 32 18 496 124 56 32
  Strain Rate (s −1 )         
Reservoir SRs 57 15 7 4 484 121 54 31
Conduit SRe 289 73 33 19 1085 272 121 68
Booster pump SRa 435 109 49 28 869 218 97 55
  Atrial volume (ml)         
  Maximum 39 10 5 3 129 33 15 9
  Minimum 85 22 10 6 159 40 18 10
  Prior to atrial contraction 89 23 10 6 147 37 17 10
  1. Presented are sample sizes required to detect a relative 5, 10, 15 or 20 % change in atrial functional parameters (with a 90 % power and an α error of 0.05).
  2. SD, standard deviation; CoV, coefficient of variation; ICC, intraclass correlation coefficient; CI, confidence interval.