Table 3.
Demographic characteristics and presence of secondary signs in patients with equivocal ultrasound studies stratified by final diagnosis.
| Overall (N = 530) | Appendicitis (N = 74) | No Appendicitis (N = 456) | p-value | ORa | 95% CI | |
|---|---|---|---|---|---|---|
| Race | ||||||
| White | 334 (63.0%) | 52 (70.3%) | 282 (61.8%) | 0.291 | Ref | - |
| Black | 137 (25.9%) | 17 (23.0%) | 120 (26.3%) | 0.49 | (0.24, 1.02) | |
| Other | 59 (11.1%) | 5 (6.8%) | 54 (11.8%) | 0.30 | (0.09, 1.01) | |
| Sex | ||||||
| Male | 193 (36.4%) | 40 (54.0%) | 153 (33.5%) | 0.001* | Ref | - |
| Female | 337 (63.6%) | 34 (46.0%) | 303 (66.5%) | 0.43 | (0.23, 0.79) | |
| Age | ||||||
| 5–9 | 160 (30.2%) | 24 (32.4%) | 136 (29.8%) | 0.179 | 1.14 | (0.50, 2.60) |
| 10–14 | 223 (42.1%) | 36 (48.7%) | 187 (41.0%) | 1.25 | (0.58, 2.69) | |
| 15+ | 147 (27.7%) | 14 (18.9%) | 133 (29.2%) | Ref | - | |
| Abn bowel wall | ||||||
| Present | 23 (4.3%) | 11 (14.9%) | 12 (2.6%) | <0.001* | 1.61 | (0.47, 5.47) |
| Absent | 507 (95.7%) | 63 (85.1%) | 12 (2.6%) | Ref | - | |
| Abn adjacent bowel | ||||||
| Present | 8 (1.5%) | 4 (5.4%) | 4 (0.9%) | 0.016* | 1.66 | (0.30, 9.32) |
| Absent | 522 (98.5%) | 70 (94.6%) | 452 (91.1%) | Ref | - | |
| Free fluid | ||||||
| Present | 28 (5.3%) | 15 (20.3%) | 13 (2.9%) | <0.001* | 9.78 | (3.76, 25.44) |
| Absent | 502 (94.7%) | 59 (79.7%) | 443 (97.1%) | Ref | - | |
| Fluid collection | ||||||
| Present | 8 (1.5%) | 6 (8.1%) | 2 (0.4%) | <0.001* | 13.31 | (2.14, 82.76) |
| Absent | 522 (98.5%) | 68 (91.9%) | 454 (99.6%) | Ref | - | |
| Abn lymph nodes | ||||||
| Present | 26 (4.9%) | 6 (8.1%) | 20 (4.4%) | 0.239 | 1.11 | (0.35, 3.63) |
| Absent | 504 (95.1%) | 68 (91.9%) | 436 (95.6%) | Ref | - | |
| Appendicolith | ||||||
| Present | 12 (2.3%) | 9 (12.2%) | 3 (0.7%) | <0.001* | 7.86 | (1.66, 37.15) |
| Absent | 518 (97.7%) | 65 (87.8%) | 453 (99.3%) | Ref | - | |
| Echogenic fat | ||||||
| Present | 10 (1.9%) | 7 (9.5%) | 3 (0.7%) | <0.001* | 4.56 | (0.73, 28.40) |
| Absent | 520 (98.1%) | 67 (90.5%) | 453 (99.3%) | Ref | - | |
| Hyperemia | ||||||
| Present | 9 (1.7%) | 7 (9.5%) | 2 (0.4%) | <0.001* | 11.97 | (1.50, 95.49) |
| Absent | 521 (98.3%) | 67 (90.5%) | 454 (99.6%) | Ref | - | |
| SS Present | ||||||
| 0 | 446 (80.0%) | 38 (51.4%) | 408 (89.5%) | <0.001* | Ref | - |
| 1 | 57 (14.0%) | 17 (23.0%) | 40 (8.8%) | 4.31 | (2.19, 8.47) | |
| 2 | 15 (3.4%) | 10 (13.5%) | 5 (1.1%) | 19.07 | (5.91, 61.55) | |
| 3+ | 12 (2.6%) | 9 (12.2%) | 3 (0.7%) | 39.17 | (9.57, 160.36) | |
a
Adjusted odds ratio (OR) for “number of secondary signs present” is adjusted for race, sex, and age. All other variables are included in a separate model and are adjusted for other secondary signs present, race, sex, and age.
Abn – abnormal, Ref – reference value, SS – secondary signs