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Table 2 Overall inter-observer contour comparison metrics

From: Cranial organs at risk delineation: heterogenous practices in radiotherapy planning

  Optimal value L_parotid L_ON Optic chiasm Brainstem Pituitary L_cochlea LIAM L_hippocampus ASLE
Experts
 Volume (cc) NA 38.2 0.5 0.3 29.2 0.2 0.1 0.3 2.1 0.9
 # slices contoured NA 25 4 2 20 3 3 2 8 5
Observers
 n NA 53 54 53 55 55 47 54 38 51
 Mean volume (cc) (SD) NA 32.4 (6.4) 1.2 (0.5) 1.1 (0.5) 24.9 (4.2) 0.4 (0.2) 0.2 (0.1) 0.9 (4.1) 3.4 (2.0) 2.1 (1.6)
 Mean # slices contoured (SD) NA 21.4 (3.5) 3.9 (1.3) 2.9 (1.5) 17.7 (3.2) 2.5 (0.6) 1.9 (1.0) 2.1 (2.0) 7.8 (1.9) 5.9 (1.8)
Observers versus expert
 Mean VR (SD) 1.0 0.9 (0.2) 2.4 (1.0) 3.2 (1.6) 0.9 (0.2) 1.7 (0.8) 1.8 (1.3) 3.4 (15.1) 1.6 (1.0) 2.3 (1.8)
 Mean VCC (SD) 1 0.76 (0.15) 0.69 (0.13) 0.56 (0.23) 0.74 (0.14) 0.74 (0.24) 0.65 (0.22) 0.56 (0.31) 0.45 (0.29) 0.82 (0.18)
 Mean VSC (SD) 0 0.11 (0.05) 0.67 (0.13) 0.77 (0.17) 0.15 (0.06) 0.50 (0.21) 0.48 (0.26) 0.41 (0.28) 0.70 (0.21) 0.46 (0.30)
 Mean OV (SD) 1.0 0.7 (0.1) 0.3 (0.1) 0.2 (0.2) 0.7 (0.1) 0.4 (0.2) 0.4 (0.2) 0.4 (0.2) 0.2 (0.2) 0.4 (0.2)
 Mean KI (SD) 1.0 0.8 (0.1) 0.4 (0.1) 0.3 (0.2) 0.8 (0.1) 0.6 (0.2) 0.5 (0.2) 0.5 (0.2) 0.3 (0.2) 0.6 (0.2)
 Global OV 1.0 0.1 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0
 Global KI 1.0 0.2 0.1 0.0 0.3 0.0 0.0 0.0 0.0 0.1
  1. Bold values refer to so-called voluminous OAR
  2. SD standard deviation, L_ON left optic nerve, LIAM left Internal acoustic meatus, ASLE anterior segment of the left eyeball, VR volume ratio, VCC volume commonly contoured, VSC volume supplementary contoured, OV overlap ratio, KI Kappa index