Table 4. Cox proportional-hazards regression analysis of factors affecting LOS in patients with burns.

Variable	Variable assignment	B	SE	Wald	P-value	HR (95%CI)
Age	Continuous variables	−0.008	0.002	10.461	0.001	0.993 (0.988–0.997)
Gender	1 = Male; 0 = Female	0.210	0.094	4.976	0.026	1.234 (1.026–1.484)
Degree of burn	Dummy variable			66.404	<0.001
Superficial partial thickness						1.00
Deep partial thickness		1.140	0.146	60.851	<0.001	3.128 (2.349–4.166)
Full thickness		0.583	0.134	19.037	<0.001	1.791 (1.379–2.327)
TBSA	Dummy variable			81.342	<0.001
<10%						1.00
10–29%		1.381	0.227	37.078	<0.001	3.978 (2.551–6.205)
≥30%		0.581	0.231	6.292	0.012	1.787 (1.135–2.813)
Etiology	1 = Heat; 0 = non-heat*	0.404	0.118	11.770	0.001	1.497 (1.189–1.886)
Skin grafting	1 = Yes; 0 = No	−1.083	0.147	54.553	<0.001	0.339 (0.254–0.451)
Inhalation burn	1 = Yes; 0 = No	0.073	0.204	0.127	0.721	1.076 (0.721–1.605)
Complications	1 = Yes; 0 = No	−0.199	0.162	1.518	0.218	0.819 (0.597–1.125)
Medical treatment ≤24 h	1 = Yes; 0 = No	−0.032	0.112	0.083	0.773	0.968 (0.777–1.207)

Notes:

Gender, TBSA, degree of burn and etiology were risk factors for LOS, while age and skin grafting were protective factors of LOS.

B, regression coefficients; SE, standard error; HR, hazard ratio; CI, confidence interval.

^*Heat etiology including hot liquid, fire, hot solids, and hot gases; all other factors were non-heat etiology.