Table 3.
Inter-reader agreement results: agreement rate and κ-value for each couple of readers in assignment of Prostate Imaging-Reporting and Data System (PI-RADS) v2.1 score. Numbers in round brackets are ratios between the number of lesions assessed with the same PI-RADS score from both readers and the total number of lesions. Numbers in square brackets are 95% confidence interval lower and upper bounds for κ-value. DCE = dynamic contrast-enhanced MRI; PCa = prostate cancer; PZ = peripheral zone; CS-PCa = clinically significant prostate cancer (defined as Gleason score > 3 + 3); R1-R2 = reader 1 and reader 2; R1-R3 = reader 1 and reader 3; R2-R3 = reader 2 and reader 3.
| PI-RADS v2.1 Type | Lesion Type | Agreement Rate, % [Number of Lesions in Agreement/Total No. of Lesions] |
κ Value [95% CI] |
||||
|---|---|---|---|---|---|---|---|
| R1-R2 | R1-R3 | R2-R3 | R1-R2 | R1-R3 | R2-R3 | ||
| with DCE | All lesions (n = 117) |
85.5 (100/117) |
91.4 (107/117) |
90 (106/117) |
0.87 [0.82–0.93] |
0.92 [0.89–0.97] |
0.92 [0.87–0.97] |
| no DCE | All lesions (n = 117) |
82 (96/117) |
86.3 (101/117) |
92.3 (108/117) |
0.86 [0.8–0.92] |
0.89 [0.84–0.94] |
0.94 [0.9–0.98] |
| with DCE | PCa lesions (n = 78) |
87.1 (68/78) |
92.3 (72/78) |
94.9 (74/78) |
0.86 [0.79–0.94] |
0.92 [0.85–0.98] |
0.95 [0.9–1.00] |
| no DCE | PCa lesions (n = 78) |
87.2 (68/78) |
87.2 (68/78) |
97.4 (76/78) |
0.89 [0.82–0.95] |
0.88 [0.82–0.95] |
0.98 [0.95–1.00] |
| with DCE | PZ PCa lesions (n = 66) |
86.4 (57/66) |
92.4 (61/66) |
93.9 (62/66) |
0.86 [0.77–0.94] |
0.92 [0.85–0.99] |
0.94 [0.89–1.00] |
| no DCE | PZ PCa lesions (n = 66) |
87.9 (58/66) |
87.9 (58/66) |
97.4 (64/66) |
0.9 [0.83–0.97] |
0.89 [0.82–0.97] |
0.97 [0.94–1.00] |
| with DCE | CS-PCa lesions (n = 41) |
95.1 (39/41) |
97.6 (40/41) |
97.6 (40/41) |
0.93 [0.84–1.00] |
0.96 [0.89–1.00] |
0.96 [0.9–1.00] |
| no DCE | CS-PCa lesions (n = 41) |
85.4 (35/41) |
85.4 (35/41) |
92.1 (39/41) |
0.84 [0.73–0.95] |
0.83 [0.71–0.95] |
0.94 [0.87–1.00] |
| with DCE | non-PCa lesions (n = 39) |
82 (32/39) |
89.7 (35/39) |
82 (32/39) |
0.78 [0.62–0.94] |
0.89 [0.79–0.99] |
0.78 [0.62–0.94] |
| no DCE | non-PCa lesions (n = 39) |
71.8 (28/39) |
84.6 (33/39) |
82 (32/39) |
0.63 [0.44–0.83] |
0.8 [0.65–0.95] |
0.78 [0.61–0.94] |