Table 2 Comparison of baseline characteristics in a post-PSM SEER cohort before and after IPTW adjustment

Age

0.0684

−0.1607

0.611

0.0493

  < 55

34 (37.8%)

35 (53.8%)

54.8 (39.4%)

51.0 (34.3%)

  > =55

56 (62.2%)

30 (46.2%)

84.4 (60.6%)

98.0 (65.7%)

Sex

0.562

0.0598

0.910

0.0163

 Female

40 (44.4%)

25 (38.5%)

60.9 (43.8%)

63.3 (42.4%)

 Male

50 (55.6%)

40 (61.5%)

78.2 (56.2%)

85.8 (57.6%)

PTS

< 0.001

0.579

 Stamoch

27 (30.0%)

11 (16.9%)

−0.1308

37.9 (27.3)

38.8 (26.1)

− 0.0049

 Small intestine

10 (11.1%)

33 (50.8%)

0.3966

26.0 (18.7)

43.0 (28.9)

0.0913

 Colorectum

53 (58.9%)

21 (32.3%)

−0.2658

75.2 (54.1)

67.1 (45.1)

−0.0864

Grade

< 0.001

0.803

 Well differentiation G1

17 (18.9%)

14 (21.5%)

0.0265

30.1 (21.6)

29.3 (19.7)

−0.0207

 Moderate differentiation G2

12 (13.3%)

45 (69.2%)

0.559

40.4 (29.0)

57.1 (38.3)

0.0947

 Poor differentiation G3

36 (40.0%)

4 (6.2%)

−0.3385

41.7 (30.0)

43.7 (29.3)

−0.0072

 NEC

25 (27.8%)

2 (3.1%)

−0.247

27.0 (19.4)

18.8 (12.6)

−0.0667

T

0.252

0.638

 T1

12 (13.3%)

9 (13.8%)

0.0051

22.4 (16.1)

15.0 (10.1)

−0.0603

 T2

40 (44.4%)

20 (30.8%)

−0.1368

54.2 (39.0)

48.1 (32.3)

−0.0643

 T3

17 (18.9%)

20 (30.8%)

0.1188

27.3 (19.6)

43.9 (29.5)

0.0962

 T4

21 (23.3%)

16 (24.6%)

0.0128

35.2 (25.3)

42.0 (28.2)

0.0284

Primary tumor size

< 0.001

−0.3573

0.293

  < 2

8 (8.9%)

29 (44.6%)

21.4 (15.4%)

35.8 (24.0%)

−0.087

  > =2

82 (91.1%)

36 (55.4%)

117.7 (84.6%)

113.2 (76.0%)

Extrahepatic metastases

0.0135

−0.1906

0.449

−0.0865

 No

59 (65.6%)

55 (84.6%)

99.9 (71.8%)

119.9 (80.4%)

 Yes

31 (34.4%)

10 (15.4%)

39.2 (28.2%)

29.1 (19.6%)