Group; no. (%) of patients* | ||||
---|---|---|---|---|
Characteristic | Derivation n = 92 | Validation n = 59 | Total n = 151 | p value† |
Demographic | ||||
Age, yr, mean ± SD | 59.6 ± 13.2 | 58.1 ± 15.6 | 59.0 ± 14.2 | 0.5 |
No. aged ≥ 65 yr | 27 (29.3) | 19 (32.2) | 46 (30.5) | 0.7 |
Sex, male | 64 (69.6) | 41 (69.5) | 105 (69.5) | > 0.9 |
Clinical | ||||
Pleuritic chest pain | 48 (52.2) | 28 (47.5) | 76 (50.3) | 0.6 |
Severe chest pain‡ | 46 (63.9) | 30 (65.2) | 76 (64.4) | 0.9 |
Dyspnea at rest | 10 (10.9) | 4 (6.8) | 14 (9.3) | 0.4 |
Dyspnea | 21 (22.8) | 12 (20.3) | 33 (21.9) | 0.8 |
Hemoptysis | 0 (0.0) | 1 (1.7) | 1 (0.7) | 0.4†† |
Mechanism of injury§ | ||||
Simple fall | 27 (29.7) | 28 (48.3) | 55 (36.9) | 0.02 |
Fall above ground level | 33 (36.3) | 16 (27.6) | 49 (32.9) | > 0.9 |
Motor vehicle crash | 21 (23.1) | 12 (20.7) | 33 (22.1) | 0.7 |
Other | 10 (11.0) | 2 (3.4) | 12 (8.1) | 0.4 |
Pre-existing comorbidity | ||||
COPD | 3 (3.3) | 2 (3.4) | 5 (3.1) | > 0.9†† |
Asthma | 4 (4.3) | 3 (5.1) | 7 (4.6) | > 0.9†† |
Osteoporosis | 4 (4.3) | 6 (10.2) | 10 (6.6) | 0.2†† |
Diabetes mellitus | 10 (10.9) | 7 (11.9) | 17 (11.3) | 0.9 |
≥1 pre-existing comorbity | 19 (20.7) | 16 (27.1) | 35 (23.2) | 0.4 |
Smoking status¶ | ||||
Former smoker | 15 (19.5) | 17 (34.0) | 32 (25.2) | 0.04 |
Current smoker | 30 (39.0) | 15 (30.0) | 45 (35.4) | 0.3 |
Never smoker | 32 (41.6) | 18 (36.0) | 50 (39.4) | 0.5 |
Alcohol intoxication | 9 (9.8) | 5 (8.5) | 14 (9.3) | 0.8 |
Pre-injury antiplatelet/anticoagulant medication | ||||
ASA | 18 (19.6) | 11 (18.6) | 29 (19.2) | 0.9 |
Clopidogrel | 0 (0.0) | 0 (0.0) | 0 (0.0) | NA |
Warfarin | 3 (3.3) | 3 (5.1) | 6 (4.0) | 0.7†† |
Any | 20 (21.7) | 13 (22.0) | 33 (21.9) | > 0.9 |
Group; no. (%) of patients* | ||||
Characteristic | Derivation n = 92 | Validation n = 59 | Total n = 151 | p value† |
Results of physical examination in emergency department | ||||
Chest abrasion | 3 (3.3) | 2 (3.4) | 5 (3.3) | > 0.9†† |
Chest contusion | 12 (13.0) | 5 (8.5) | 17 (11.3) | 0.4 |
Clinical rib fracture | 36 (39.1) | 31 (52.5) | 67 (44.4) | 0.1 |
Bone crepitus | 3 (3.3) | 1 (1.7) | 4 (2.6) | > 0.9†† |
Other | 17 (18.5) | 17 (28.8) | 34 (22.5) | 0.1 |
Vital signs, mean ± SD | ||||
Heart rate, beats/min | 80.3 ± 12.8 | 79.3 ± 15.7 | 79.9 ± 14.0 | 0.7 |
Oxygen saturation, % | 97.2 ± 2.1 | 97.2 ± 1.9 | 97.2 ± 2.0 | 0.9 |
Respiratory rate, breaths/min | 18.3 ± 3.3 | 17.6 ± 3.3 | 18.0 ± 3.3 | 0.3‡‡ |
No. of rib fractures** | ||||
None | 30 (32.6) | 19 (32.2) | 49 (32.5) | > 0.9 |
1 | 21 (22.8) | 10 (16.9) | 31 (20.5) | 0.4 |
2 | 13 (14.1) | 13 (22.0) | 26 (17.2) | 0.2 |
≥ 3 | 28 (30.4) | 17 (28.8) | 45 (29.8) | 0.8 |
Location of fracture** | ||||
Any high rib (3-5) | 22 (23.9) | 14 (23.7) | 36 (23.8) | > 0.9 |
Any mid rib (6-9) | 52 (56.5) | 32 (54.2) | 84 (55.6) | 0.8 |
Any high or mid rib (3-9) | 60 (65.2) | 38 (64.4) | 98 (64.9) | 0.9 |
Any low rib (10-12) | 14 (15.2) | 9 (15.3) | 23 (15.2) | > 0.9 |
Atelectasis† | 18 (19.6) | 10 (16.9) | 28 (18.5) | 0.7 |
Note: ASA = acetylsalicylic acid, COPD = chronic obstructive pulmonary disease, SD = standard deviation.
*Except where indicated otherwise.
†All statistical analyses were performed with the Student t test or χ2 test, except where indicated otherwise.
‡For severe chest pain, data were available for 72 patients in the derivation group and 46 patients in the validation group (118 patients total).
§For mechanism of injury, data were available for 91 patients in the derivation group and 58 patients in the validation group (149 total). Here, the category "other" incorporates data for pedestrian v. car, cyclist v. car and direct hit (these categories are reported separately in Table 1).
¶For smoking status, data were available for 77 patients in the derivation group and 50 patients in the validation group (127 patients total).
**Number and location of fractures were confirmed by initial radiography.
††Fisher exact test.
‡‡Wilcoxon test.