Table 4. Logistic regression analysis of right CLNM and PRRLN-LNM with high risk factors.

Characteristic	HR	95% CI	P
Presence of right CLNM
Age (years)
<45	1	–	–
46–59	0.926	0.541–1.583	0.778
≥60	0.250	0.071–0.879	0.031*
Gender
Male	1	–	–
Female	0.449	0.252–0.802	0.007**
Maximal tumor size, cm
≥0.5	1	–	–
<0.5	0.312	0.163–0.600	<0.001***
Presence of PRRLN-LNM
Age (years)
<45	1	–	–
46–59	0.308	0.113–0.836	0.021*
≥60	0.164	0.020–1.366	0.095
Gender
Male	1	–	–
Female	0.373	0.160–0.874	0.023*
Maximal tumor size, cm
≥0.5	1	–	–
<0.5	0.287	0.082–1.001	0.050
Capsular invasion
Present	1	–	–
Absent	0.240	0.096–0.601	0.002**

*, P<0.05; **, P<0.01; ***, P<0.001. HR, high risk; CI, confidence interval; CLNM, central lymph node metastasis; PRRLN-LNM, posterior right recurrent laryngeal nerve lymph node metastasis.