Table 1 Patient characteristics for before SIPTW adjustment and after SIPTW adjustment

^Age

⁵⁹

⁵⁷

^0.210

^0.114

⁵⁹

⁵⁸

^0.821

^0.006

^{(Median [IQR] year)}

^{[53.00, 63.25]}

^{[53.00, 62.00]}

^{[53.00, 63.00]}

^{[53.00, 63.00]}

^{Adjuvant treatment (%)}

^0.292

^0.124

^0.897

^0.015

^No

^{125 (57.9)}

^{76 (51.7)}

^{117.5 (54.4)}

^{79.3 (53.7)}

^Yes

^{91 (42.1)}

^{71 (48.3)}

^{98.4 (45.6)}

^{68.5 (46.3)}

^{ASA (%)}

^0.513

^0.123

^0.990

^0.016

^I

^{38 (17.6)}

^{21 (14.3)}

^{35.3 (16.4)}

^{23.3 (15.8)}

^Ii

^{158 (73.1)}

^{108 (73.5)}

^{158.5 (73.4)}

^{109.5 (74.1)}

^Iii

^{20 ( 9.3)}

^{18 (12.2)}

^{22.0 (10.2)}

^{15.0 (10.2)}

^BMI

^22.1

^22.5

^0.717

^0.076

^22.1

^22.1

^0.525

^0.021

^{(Median [IQR] kg/m2)}

^{[20.10, 24.83]}

^{[20.30, 24.20]}

^{[20.20, 24.99]}

^{[20.22, 24.10]}

^{Blood transfusion (%)}

^0.310

^0.145

^0.774

^0.039

^No

^{206 (95.4)}

^{144 (98.0)}

^{207.8 (96.3)}

^{141.2 (95.5)}

^Yes

^{10 ( 4.6)}

^{3 ( 2.0)}

^{8.0 ( 3.7)}

^{6.6 ( 4.5)}

^{Cardiovascular disease (%)}

^1.000

^0.031

^0.963

^0.005

^No

^{209 (96.8)}

^{143 (97.3)}

^{209.3 (97.0)}

^{143.5 (97.1)}

^Yes

^{7 ( 3.2)}

^{4 ( 2.7)}

^{6.5 ( 3.0)}

^{4.3 ( 2.9)}

^{Cerebrovascular disease (%)}

^0.476

^0.099

^0.934

^0.009

^No

^{205 (94.9)}

^{136 (92.5)}

^{203.3 (94.2)}

^{138.9 (94.0)}

^Yes

^{11 ( 5.1)}

^{11 ( 7.5)}

^{12.5 ( 5.8)}

^{8.9 ( 6.0)}

^{Drink (%)}

^0.401

^0.103

^0.880

^0.018

^No

^{75 (34.7)}

^{44 (29.9)}

^{70.4 (32.6)}

^{49.4 (33.4)}

^Yes

^{141 (65.3)}

^{103 (70.1)}

^{145.5 (67.4)}

^{98.4 (66.6)}

^{Diabetes (%)}

^0.114

^0.192

^0.657

^0.056

^No

^{212 (98.1)}

^{139 (94.6)}

^{205.7 (95.3)}

^{142.5 (96.4)}

^Yes

^{4 ( 1.9)}

^{8 ( 5.4)}

^{10.1 ( 4.7)}

^{5.3 ( 3.6)}

^{Duration of anesthesia}

^6.1

^6.3

^0.189

^0.178

^6.23

^6.2

^0.886

^0.002

^{(Median [IQR] h)}

^{[5.00, 7.00]}

^{[5.20, 7.35]}

^{[5.00, 7.00]}

^{[5.00, 7.30]}

^{Degree of differentiation (%)}

^0.777

^0.044

^0.884

^0.017

^Poor

^{165 (76.4)}

^{115 (78.2)}

^{165.4 (76.6)}

^{114.3 (77.3)}

^Well

^{51 (23.6)}

^{32 (21.8)}

^{50.5 (23.4)}

^{33.5 (22.7)}

^{Hypertension (%)}

^0.182

^0.157

^0.974

^0.004

^No

^{186 (86.1)}

^{118 (80.3)}

^{181.0 (83.9)}

^{124.2 (84.0)}

^Yes

^{30 (13.9)}

^{29 (19.7)}

^{34.8 (16.1)}

^{23.7 (16.0)}

^{N (%)}

^0.009

^0.329

^0.985

^0.020

^N0

^{117 (54.2)}

^{61 (41.5)}

^{103.7 (48.0)}

^{70.6 (47.8)}

^N1

^{58 (26.9)}

^{62 (42.2)}

^{72.2 (33.4)}

^{48.7 (32.9)}

^N2

^{41 (19.0)}

^{24 (16.3)}

^{40.0 (18.5)}

^{28.5 (19.3)}

^{Postoperative hospital stay}

¹⁶

¹⁵

^0.906

^0.038

¹⁶

¹⁵

^0.921

^0.010

^{(Median [IQR] d)}

^{[14.00, 18.25]}

^{[14.00, 18.50]}

^{[14.00, 18.00]}

^{[14.00, 18.38]}

^{Preoperative HB}

^146.5

^145.1

^0.909

^0.035

^146.64

¹⁴⁵

^0.761

^0.023

^{(Median [IQR] g/l)}

^{[135.93, 154.00]}

^{[137.00, 154.40]}

^{[136.23, 154.21]}

^{[136.44, 154.76]}

^{Pathological classification (%)}

^0.590

^0.100

^0.636

^0.051

^{Adenocarcinoma}

^{6 ( 2.8)}

^{2 ( 1.4)}

^{4.5 ( 2.1)}

^{2.1 ( 1.4)}

^{Squamous cell carcinoma}

^{210 (97.2)}

^{145 (98.6)}

^{211.3 (97.9)}

^{145.7 (98.6)}

^{Sex (%)}

^1.000

^0.003

^0.931

^0.009

^Female

^{6 ( 2.8)}

^{4 ( 2.7)}

^{5.3 ( 2.4)}

^{3.4 ( 2.3)}

^Male

^{210 (97.2)}

^{143 (97.3)}

^{210.6 (97.6)}

^{144.4 (97.7)}

^{Smoke (%)}

^0.333

^0.116

^0.919

^0.012

^No

^{84 (38.9)}

^{49 (33.3)}

^{78.0 (36.1)}

^{52.6 (35.6)}

^Yes

^{132 (61.1)}

^{98 (66.7)}

^{137.8 (63.9)}

^{95.2 (64.4)}

^{The length of the operation}

^5.2

^5.3

^0.160

^0.194

^5.2

^5.11

^0.756

^0.004

^{(Median [IQR] h)}

^{[4.07, 6.10]}

^{[3.95, 6.40]}

^{[4.10, 6.20]}

^{[3.80, 6.17]}

^{Surgical type (%)}

^0.835

^0.095

^0.988

^0.039

^{Lvor lewis}

^{86 (39.8)}

^{58 (39.5)}

^{83.6 (38.7)}

^{54.8 (37.1)}

^Mckeown

^{55 (25.5)}

^{37 (25.2)}

^{54.7 (25.3)}

^{38.4 (26.0)}

^Sweet

^{74 (34.3)}

^{50 (34.0)}

^{76.3 (35.4)}

^{53.5 (36.2)}

^{Thoracoabdominal incision}

^{1 ( 0.5)}

^{2 ( 1.4)}

^{1.2 ( 0.6)}

^{1.1 ( 0.7)}

^{Tumor location (%)}

^0.739

^0.083

^0.956

^0.035

^{Lower esophagus}

^{96 (44.4)}

^{67 (45.6)}

^{96.5 (44.7)}

^{64.0 (43.3)}

^{Middle esophagus}

^{105 (48.6)}

^{67 (45.6)}

^{100.7 (46.6)}

^{69.9 (47.3)}

^{Upper esophagus}

^{15 ( 6.9)}

^{13 ( 8.8)}

^{18.7 ( 8.6)}

^{14.0 ( 9.4)}

^{T (%)}

^0.884

^0.086

^0.986

^0.040

^T1

^{51 (23.6)}

^{32 (21.8)}

^{48.6 (22.5)}

^{34.6 (23.4)}

^T2

^{40 (18.5)}

^{32 (21.8)}

^{44.1 (20.4)}

^{31.7 (21.4)}

^T3

^{121 (56.0)}

^{80 (54.4)}

^{119.5 (55.4)}

^{79.4 (53.7)}

^T4

^{4 ( 1.9)}

^{3 ( 2.0)}

^{3.6 ( 1.7)}

^{2.1 ( 1.5)}

^{TNM (%)}

^0.261

^0.177

^0.999

^0.004

^I

^{46 (21.3)}

^{23 (15.6)}

^{39.9 (18.5)}

^{27.5 (18.6)}

^Ii

^{75 (34.7)}

^{48 (32.7)}

^{72.0 (33.4)}

^{49.2 (33.3)}

^Iii

^{95 (44.0)}

^{76 (51.7)}

^{104.0 (48.2)}

^{71.1 (48.1)}

^{Total hospital stay}

²⁴

²⁴

^0.627

^0.029

²⁴

²⁴

^0.567

^0.017

^{(Median [IQR] d)}

^{[21.00, 28.00]}

^{[21.00, 28.50]}

^{[21.00, 27.04]}

^{[21.00, 29.00]}