Table 3.
CT results and inter-reader agreement (Fleiss kappa).
| CT results | All (n = 160) | COVID-19 (n = 79) | Control (n = 81) | Fleiss kappa [95% CI] |
|---|---|---|---|---|
| All categories | 0.527 [0.490-0.564] | |||
| Typical | 0.648 [0.584-0.711] | |||
| Reader 1 | 39 | 39 (49.4) | 0 (0.0) | |
| Reader 2 | 33 | 31 (39.2) | 2 (2.5) | |
| Reader 3 | 56 | 54 (68.4) | 2 (2.5) | |
| Reader 4 | 42 | 41 (51.9) | 1 (1.2) | |
| Indeterminate | 0.383 [0.320-0.446] | |||
| Reader 1 | 61 | 35 (44.3) | 26 (32.1) | |
| Reader 2 | 33 | 29 (36.7) | 4 (4.9) | |
| Reader 3 | 34 | 19 (24.1) | 15 (18.5) | |
| Reader 4 | 49 | 31 (39.2) | 18 (22.2) | |
| Atypical | 0.565 [0.502-0.629] | |||
| Reader 1 | 50 | 3 (3.8) | 47 (58.0) | |
| Reader 2 | 54 | 11 (13.9) | 43 (53.1) | |
| Reader 3 | 50 | 5 (6.3) | 45 (55.6) | |
| Reader 4 | 32 | 2 (2.5) | 30 (37.0) | |
| Negative | 0.510 [0.447-0.573] | |||
| Reader 1 | 10 | 2 (2.5) | 8 (9.9) | |
| Reader 2 | 40 | 8 (10.1) | 32 (39.5) | |
| Reader 3 | 20 | 1 (1.3) | 19 (23.5) | |
| Reader 4 | 37 | 5 (6.3) | 32 (39.5) |
Notes: Qualitative variables are expressed as absolute and relative frequencies (n [%]). Percentages (%) shown are relative to the number of the respective category assigned within each group (i.e., COVID-19 and control) by each reader. The reported Fleiss kappa values are for all readers when all categories are considered simultaneously, as well as for each category individually.