Table 2.

Factors affecting the number of retrieved lymph nodes.

Factors	n	IRR (95 % CI)	p-Value a
Age
⩽60	24	1.225 (1.136–1.321)	<0.01*
>60	21	Ref
Gender
Male	25	1.044 (0.968–1.125)	0.262
Female	20	Ref
ASA
1	30	Ref
2	12	0.76 (0.69–0.83)	<0.01*
3	3	0.81 (0.70–0.95)	<0.01*
NRS/Q-SGA
A	24	Ref
B	17	0.91 (0.84–0.99)	0.023*
C	4	0.81 (0.70–0.93)	0.004*
Tumor location
Cecum	7	Ref
Ascending	6	0.94 (0.83–1.07)	0.366
Hepatic flexure	8	0.82 (0.72–0.92)	0.001*
Transverse	2	0.68 (0.55–0.84)	<0.001*
Splenic flexure	2	0.55 (0.44–0.69)	<0.001*
Descending	3	0.91 (0.78–1.06)	0.230
Sigmoid	17	0.66 (0.59–0.73)	<0.001*
CEA level
Non elevated ⩽5 ng/ml	26	Ref
Evaluated	19	1.07 (0.99–1.15)	0.088
pT
1	2	0.57 (0.44–0.73)	<0.001*
2	21	0.95 (0.83–1.08)	0.398
3	18	0.82 (0.72–0.93)	0.003*
4	4	Ref
pN
No	28	1.13 (1.04–1.22)	0.003*
N1–3	17	Ref
AJCC 8th stage
I	20	1
II	8	0.88 (0.79–0.98)	0.016*
III	17	0.86 (0.79–0.93)	<0.01*
Histology
High	34	Ref
Moderate	9	0.82 (0.74–0.90)	<0.01*
Low	2	0.92 (0.77–1.11)	0.383
Tumor size
⩽4.5	26	Ref
>4.5	19	1.22 (1.14–1.32)	<0.01*
Specimen length
⩽25	17	Ref
>25	28	1.14 (1.05–1.23)	0.001*

^aNegative binomial with log link.

^*p < 0.05.