Table. Overall Prevalence of Artifacts and Severity Between Scan Sizes.
| Artifact | Mild or Moderate | Severe | ||||
|---|---|---|---|---|---|---|
| No. (%) | P Value | No. (%) | P Value | |||
| 3 mm × 3 mm (n = 185) | 6 mm × 6 mm (n = 221) | 3 mm × 3 mm (n = 185) | 6 mm × 6 mm (n = 221) | |||
| Movement | 133 (71.9) | 180 (81.4) | .02 | 43 (23.2) | 22 (9.9) | <.001 |
| Defocus | 90 (48.6) | 129 (58.4) | .051 | 30 (16.2) | 55 (24.9) | .03 |
| Shadow | 40 (21.6) | 106 (48.0) | <.001 | 39 (21.1) | 68 (30.8) | .03 |
| Tilt | 75 (40.5) | 105 (47.5) | .16 | 1 (0.5) | 24 (10.9) | <.001 |
| Z offset | 43 (23.2) | 120 (54.3) | <.001 | 14 (7.6) | 1 (0.5) | <.001 |
| Refraction shift | 54 (29.2) | 62 (28.1) | .80 | 6 (3.2) | 7 (3.2) | .97 |
| Segmentation error | 29 (15.7) | 61 (27.6) | .004 | 3 (1.6) | 7 (3.2) | .32 |
| Decentration | 15 (8.1) | 36 (16.3) | .01 | 32 (17.3) | 4 (1.8) | <.001 |
| Projection | 6 (3.2) | 21 (9.5) | .01 | 0 | 0 | NA |
| Total | 178 (96.2) | 216 (97.7) | .37 | 105 (56.8) | 112 (50.7) | .22 |
Abbreviation: NA, not applicable.