Table 3.

Multivariate logistic regression analysis of predictors of BEO.

Feature	Reference group	OR (95% CI)	p-value
Fatigue	No	0.43 (0.23, 0.81)	0.008
Lumbago	No	0.41 (0.21, 0.82)	0.011
WBC		1.13 (1.02, 1.25)	0.019
PLT		1.00 (1.00, 1.01)	0.066
ESR		1.01 (1.00, 1.02)	0.132
Positive blood culture	No	1.77 (1.03, 3.04)	0.038
Symptom duration, per 30 days		1.00 (0.92, 1.08)	0.977

Model performance: Hosmer–Lemeshow goodness-of-fit test, χ² = 21.98, df = 8, p = 0.079, discrimination (AUC) = 0.68; Nagelkerke R² = 0.09. Multicollinearity assessed by variance inflation factor (VIF): all VIF < 1.3 (maximum VIF = 1.20), indicating negligible collinearity.