Table 1.

Sensitivity analysis among groups.

	Studies	Patients(LND+/LND−)	Total	OR	P-value	Study heterogeneity
						I²	p
Studies with sample size greater than 200
1-year OS	7	1,125/1,001	2,126	0.81	0.05	9%	0.36
3-year OS	7	1,125/1,001	2,126	0.78	0.01	35%	0.16
5-year OS	7	1,125/1,001	2,126	0.76	0.007	43%	0.10
1-year DFS	2	290/157	447	0.52	0.01	69%	0.07
3-year DFS	2	290/157	447	0.50	0.001	3%	0.31
5-year DFS	2	290/157	447	0.47	0.0007	0%	0.32
Multi-center studies
1-year OS	6	995/606	1601	0.85	0.45	51%	0.07
3-year OS	6	995/606	1601	0.94	0.76	73%	0.002
5-year OS	6	995/606	1601	0.82	0.33	66%	0.01
1-year DFS	2	233/111	344	0.82	0.81	91%	0.0008
3-year DFS	2	233/111	344	0.82	0.81	91%	0.0008
5-year DFS	2	233/111	344	0.64	0.45	80%	0.02
Studies from East Asia
1-year OS	13	1,092/1,116	2208	0.74	0.04	36%	0.09
3-year OS	13	1,092/1,116	2208	0.82	0.40	79%	<0.00001
5-year OS	13	1,092/1,116	2208	0.69	0.01	70%	0.0002
1-year DFS	3	324/191	515	0.71	0.39	72%	0.03
3-year DFS	3	324/191	515	0.72	0.44	75%	0.02
5-year DFS	3	324/191	515	0.73	0.51	80%	0.008
High-quality studies (score ≥ 6)
1-year OS	6	381/684	1065	0.87	0.38	44%	0.11
3-year OS	6	381/684	1065	1.20	0.48	74%	0.002
5-year OS	6	381/684	1065	1.19	0.37	50%	0.08
1-year DFS	3	130/105	235	1.56	0.11	0%	0.43
3-year DFS	3	130/105	235	1.72	0.05	0%	0.49
5-year DFS	3	130/105	235	1.47	0.17	0%	0.53
Studies published after 2018
1-year OS	7	926/519	1445	0.97	0.91	58%	0.03
3-year OS	7	926/519	1445	1.49	0.26	87%	<0.00001
5-year OS	7	926/519	1445	0.96	0.88	77%	0.0005
1-year DFS	3	267/145	412	1.02	0.97	85%	0.001
3-year DFS	3	267/145	412	1.13	0.84	85%	0.001
5-year DFS	3	267/145	412	0.96	0.94	82%	0.004

OR, odds ratio; OS, overall survival; DFS, disease-free survival; LND, lymph node dissection.