Table 1.

Patient characteristics in the derivation and validation set

	Derivation set (n = 2555)	Validation set (n = 685)	P Value
Age, years, No. (%)	68 (61—77)	68 (60—77)	0.58
Sex, male, No. (%)	1182 (46.3%)	312 (45.5%)	0.77
PE severity grade, No. (%)
Severe	353 (13.8%)	88 (12.8%)	0.79
Moderate	140 (5.5%)	38 (5.5%)
Mild	93 (3.6%)	21 (3.1%)
No PE	1969 (77.1%)	538 (78.5%)
Symptoms, No. (%)
Anhelation	671 (26.3%)	186 (27.2%)	0.67
Lower limb edema	81 (3.2%)	31 (4.5%)	0.11
Chest distress	840 (32.9%)	214 (31.2%)	0.44
Chest pain	764 (29.9%)	210 (30.7%)	0.74
Hemoptysis	35 (1.4%)	9 (1.3%)	> 0.99
Syncope	188 (7.4%)	53 (7.7%)	0.80
Cough	60 (2.3%)	20 (2.9%)	0.47
Palpitation	248 (9.7%)	68 (9.9%)	0.92
Signs, median (IQR)
Temperature, ℃	36.5 (36.2—36.8)	36.5 (36.2—36.7)	0.30
Heart rate, beats/min	88 (77—103)	88 (76—102)	0.91
Systolic blood pressure, mmHg	140 (122—158)	139 (120—156)	0.82
Diastolic blood pressure, mmHg	76 (66—86)	76 (67—86)	0.70
Oxygen saturation, %	96 (94—98)	96 (94—98)	0.67
Past medical history, No. (%)
Cancer	86 (3.4%)	32 (4.7%)	0.13
Pulmonary embolism	61 (2.4%)	21 (3.1%)	0.39
Immobilization	584 (22.9%)	144 (21.0%)	0.33
Hypertension	423 (16.6%)	102 (14.9%)	0.15

Data are n (%), median (IQR), or mean (SD). Patients were randomly divided into the derivation and validation set using a stratified randomization scheme. P values were obtained using student t test for normally distributed variables, Wilcoxon rank sum test for skewed distributed variables and Chi-square (or Fisher’s exact) test for categorical variables