Table 3.

Univariate and multivariate Cox regression analyses of risk factors for negative conversion time

	Univariate analysis				Multivariate analysis
	HR	95%CI	P value		HR	95%CI	P value
< 35 years
Medical staff (no vs. yes)	0.55	(0.39, 0.78)	< 0.001		0.53	(0.39, 0.76)	< 0.001
Dietary pattern C
T1	Reference				Reference
T2	1.49	(1.11, 1.99)	< 0.01		1.35	(1.00, 1.81)	< 0.05
T3	1.55	(1.12, 2.16)	< 0.01		1.40	(1.00, 1.97)	< 0.05
Treatment
None	Reference				Reference
Self-medication	1.07	(0.76, 1.51)	0.703		1.01	(0.71, 1.43)	0.95
Medical prescription	0.53	(0.30, 0.95)	< 0.05		0.48	(0.26, 0.86)	< 0.05
35 ~ 45 years
Region (north vs. south)	0.31	(0.16, 0.59)	< 0.001		0.46	(0.23, 0.93)	< 0.05
Medical staff (no vs. yes)	0.60	(0.42, 0.86)	< 0.01		0.74	(0.51, 1.08)	0.120
Sleeping hours
< 6 h	Reference				Reference
6–7 h	1.35	(0.85, 2.15)	0.279		1.38	(0.86, 2.22)	0.176
≥7 h	1.92	(1.18, 3.11)	< 0.01		1.79	(1.09, 2.95)	< 0.05
Physical exercise (no vs. yes)	1.47	(1.01, 2.14)	< 0.05		1.48	(1.02, 2.17)	< 0.05
Dietary pattern A
T1	Reference				Reference
T2	0.50	(0.33, 0.78)	< 0.01		0.50	(0.32, 0.78)	< 0.01
T3	1.04	(0.69, 1.58)	0.840		0.91	(0.59, 1.40)	0.661
≥ 45 years
Medical staff (no vs. yes)	0.59	(0.42, 0.84)	< 0.01		0.62	(0.44, 0.89)	< 0.01
Physical exercise (no vs. yes)	1.53	(1.07, 2.19)	< 0.05		1.48	(1.03, 2.11)	< 0.05
Sleeping hours
< 6 h	Reference				Reference
6–7 h	1.40	(0.93, 2.10)	0.110		1.38	(0.91, 2.09)	0.223
≥7 h	1.56	(1.00, 2.42)	< 0.05		1.46	(0.94, 2.28)	0.092

Notes: Dietary Pattern A including cereals and starch, vegetables and fruits, and seafood. Dietary pattern C was characterized by milk and dairy products, eggs and related products

Abbreviations: HR, hazard ratio; CI, confidence interval; T, tertiles