Table S1. Balance measured by standardized mean differences before and after matching.

Variables	Total data set				Matched data set			Percent balance improvement
	Means IMA	Means NMA	Standardized mean Diff		Means IMA	Means NMA	Standardized mean Diff
Distance	0.0214	0.0149	0.6413		0.0214	0.0214	−0.0017	99.7335
T1	0.3635	0.4567	−0.1937		0.3635	0.3641	−0.0013	99.3268
T2	0.5160	0.4094	0.2131		0.5160	0.5078	0.0163	92.3447
T3	0.0716	0.0706	0.0038		0.0716	0.0810	−0.0365	−872.6406
T4	0.0490	0.0633	−0.0663		0.0490	0.0471	0.0087	86.8479
N1	0.0395	0.1380	−0.5046		0.0395	0.0358	0.0193	96.1735
N2	0.0433	0.1360	−0.4550		0.0433	0.0471	−0.0185	95.9375
N3	0.0000	0.0031	−		0.0000	0.0000	–	100.0000
6th AJCC system	0.5480	0.3928	0.3116		0.5480	0.5524	−0.0088	97.1690
7th AJCC system	0.2599	0.3868	−0.2891		0.2599	0.2655	−0.0129	95.5487

AJCC, American Joint Committee on Cancer; Diff, differences; IMA, invasive mucinous adenocarcinoma; NMA, nonmucinous adenocarcinoma.