Table 1.

Patient characteristics before and after propensity score matching.

Characteristics	Before matching				After matching
	Wedge	Segment	p-value	SD (%)	Wedge	Segment	p-value	SD (%)
Total number	2360	686			686	686
Age (years)	70 (25–91)	69 (37–91)	0.160	−5.309	69 (36–91)	69 (37–91)	0.251	−6.078
Removed lymph nodes	1 (0–90)	3 (0–54)	< 0.001*	35.745	1 (0–90)	3 (0–54)	< 0.001*	25.641
Sex			0.320				0.739
Male	972	268		−4.325	262	268		1.796
Female	1388	418		4.325	424	418		−1.796
Laterality			0.006*				0.627
Left	1000	331		11.828	340	331		−2.625
Right	1360	355		−11.828	346	355		2.625
Race			0.200				0.781
White	2010	592		3.225	600	592		−3.455
Black	223	50		−7.808	49	50		0.563
Other	120	43		5.116	37	43		3.733
Unknown	7	1		−3.211	0	1		5.403
Marital status			0.180				0.880
Married	1273	396		7.628	387	396		2.651
Unmarried	972	263		−5.822	272	263		−2.690
Unknown	115	27		−4.568	27	27		0
Year at diagnosisa			0.001*				0.126
Statea			< 0.001*				0.959
Surgical lobe			< 0.001*				0.699
Upper	1508	411		−8.215	425	411		−4.184
Middle	104	10		−17.547	10	10		0.000
Lower	719	262		16.327	250	262		3.617
Overlapping	6	0		−7.140	0	0		0
Unknown	23	3		−6.420	1	3		5.409
Grade			0.463				0.661
I	649	179		−3.177	191	179		−3.942
II	1038	336		10.031	323	336		3.794
III	496	129		−5.542	131	129		−0.744
IV	15	4		−0.675	6	4		−3.428
Unknown	162	38		−5.496	35	38		1.949
Stage			< 0.001*				0.664
IA1	535	111		−16.457	110	111		0.397
IA2	1342	393		0.857	385	393		2.354
IA3	483	182		14.340	191	182		−2.949
Cause of death			0.004*				0.002*	0.001
Alive	1567	501		14.475	448	501		16.789
Lung cancer	417	112		−3.576	118	112		−2.342
COPD	89	14		−10.315	36	14		−17.177
CVD	112	19		−10.405	30	19		−8.649
Other diseases	175	40		−6.374	54	40		−8.085

Wedge, patients with wedge resection; Segment, patients with segmentectomy; SD, standardized difference; COPD, chronic obstructive pulmonary disease; CVD, cardiovascular disease. The variable of age is presented as median and range because it is not normal distribution.

^aDetailed data of year at diagnosis and state are listed in Table S1.

^*Indicates p < 0.05.