Table 4.

Analysis of the association between characteristics of patients and the number of lymph nodes harvested.

Characteristics	B	SE	P value
Univariate analysis
Age	-0.102	0.032	0.001
Sex (female vs male)	-0.011	0.627	0.987
BMI (≥25 vs<25)	-0.222	0.610	0.716
Distance from anal verge	-0.068	0.130	0.602
Tumor differentiation (poor vs well/moderate)	1.637	0.886	0.066
Clinical T stage (T3-4 vs T2)	1.005	2.000	0.616
Clinical N stage (N+ vs N0)	1.847	1.097	0.093
Radiotherapy (long vs short-term)	-2.588	1.173	0.028
nCRT regimens (oxaliplatin-containing vs capecitabine)	1.072	0.779	0.170
Period of operation (2016-2018 vs 2010-2015)	0.568	0.618	0.358
Type of surgery (no preserving vs sphincter-preserving)	0.058	0.604	0.924
Surgeons (senior vs junior)	-0.010	0.892	0.991
Operative time	-0.001	0.005	0.915
Estimated blood loss	-0.005	0.005	0.357
TRG (3 vs 2, 1 vs 0)	1.849	0.634	0.004
ypT stage (T3-4 vs T1-2 vs T0)	0.610	0.403	0.131
ypN stage (N2 vs N1 vs N0)	1.575	0.488	0.001
TME quality (Incomplete vs nearly vs complete)	0.617	0.681	0.366
Positive CRMs (yes vs no)	2.009	1.325	0.131
Lymphovascular invasion (yes vs no)	0.479	1.643	0.771
Perineural invasion (yes vs no)	0.020	1.038	0.985
Tumor deposit (yes vs no)	-1.587	1.075	1.141
Multivariate analysis
Age	-0.102	0.031	0.001
TRG (3 vs 2, 1 vs 0)	1.512	0.636	0.018
ypN stage(N2 vs N1 vs N0)	1.227	0.491	0.013

BMI, body mass index; nCRT, neoadjuvant chemoradiotherapy; TRG, tumor regression grade; TME, total mesorectal excision; CRM, circumferential resection margin.

Variables with P values in bold are included in the multivariate analysis.