Table 2. Clinical characteristics of the two groups before and after matching.

GROUPS	BEFORE MATCHING				AFTER MATCHING
	Group 1 n (%)	Group 2 n (%)	P		Group 1 n (%)	Group 2 n (%)	P
Sex			0.18				0.04
Male	234 (83)	32(76)			75 (89)	32 (76)
Female	48(17)	10(24)			9(11)	10(24)
Tumor Side			0.07				0.26
Right	149 (53)	26(62)			46(55)	26 (62)
Left	133(47)	16 (38)			38(45)	16 (38)
Type of Resection			0.11				0.43
Lobectomy	197 (70)	29(69)			65(77)	29 (69)
Pneumonectomv	44(15.8)	3(7)			14(17)	3(7)
Sublobar	18 (6.2)	6(15)			2(2.5)	6(15)
VATS Lobectomv	23 (8)	4(10)			3(3.5)	4(10)
Size of Tumor	4.4=2.12	4.3±2.37	0.77		4.2±2.36	4.3±2.37	0.74
Tumor Histology			0.001				0.35
Squamous	130(48)	18(43)			44(52)	18(43)
Non-Squamous	141 (52)	24(57)			40 (48)	24(57)
T Status			0.68				0.8
T1	56 (20)	11(26)			20 (24)	11(26)
T2	124 (44)	21 (49)			39(46)	21 (49)
T3	76(27)	8(21)			18(21)	8(21)
T4	26(9)	2(4)			7(9)	2(4)
N Status			0.85				0.9
NO	177(63)	28(66)			60(71)	28(66)
N1	90(32)	12(30)			21(25)	12(30)
N2	15(5)	2(4)			3(4)	2(4)
FEV1	1.94=0.78	1.72=0.46	0.01		1.83=0.43	1.72=0.46	0.04
FEYl %	75.54±18.67	S9.57±23.47	0.008		78.62=19.04	89.57±23.47	0.07
Pa02 (mmHg)	80.66=11.05	78.25dbl3.38	0.19		71.21±14.42	78.25il3.38	0.53
Comorbidites	187 (69)	32 (72)	0.73		60 (71)	32 (72)	0.89
Cardiac	143 (53)	25(55)			43 (51)	: -
Respiratory	89 (34)	13(29)			26(31)	13(29)
Renal	14(5)	3(6)			4(5)	3(6)
Neurologic	11(4)	1(2)			2(2.3)	1 C)
Metabolic (DM)	54 (20)	10(23)			18(21)	10(23)

FEV1: forced expiratory volume in one second; VATS: video-assisted thoracoscopic surgery