Table 2 Summary of characteristics between High ALI group and Low ALI group

Age

 Young

8

Reference

Reference

Reference

Reference

 Old

8

2056/ 1426

0.74 [0.64, 0.85]; P < 0.0001

FE

I² = 0%; P = 0.83

Sex

 Female

8

Reference

Reference

Reference

Reference

 Male

8

1799/ 1238

0.49 [0.25, 0.98]; P = 0.04

RE

I² = 92%; P < 0.00001

CEA

 ≤ 5

6

Reference

Reference

Reference

Reference

 > 5

6

1359/ 1014

0.74 [0.49, 1.11]; P = 0.15

RE

I² = 78%; P = 0.0003

CA 19–9

 ≤ 37

3

Reference

Reference

Reference

Reference

 > 37

3

774/ 496

0.87 [0.65, 1.16]; P = 0.35

FE

I² = 20%; P = 0.29

Preoperative anemia

2

242/ 215

0.53 [0.36, 0.78]; P = 0.001

FE

I² = 0%; P = 0.96

Chemotherapy

5

878/ 832

0.75 [0.61, 0.92]; P = 0.006

FE

I² = 0%; P = 0.47

Lymph node metastasis

3

936/ 535

1.00 [0.78, 1.28]; P = 0.98

FE

I² = 37%; P = 0.20

Vessel invasion

4

950/ 612

0.78 [0.60, 1.02]; P = 0.07

FE

I² = 0%; P = 0.75

Neural invasion

3

372/ 384

0.75 [0.51, 1.12]; P = 0.16

FE

I² = 3%; P = 0.36

Distant metastasis

3

777/ 492

0.42 [0.26, 0.66]; P = 0.0002

RE

I² = 52%; P = 0.13

Histology

 Well/ Moderate

7

Reference

Reference

Reference

Reference

 Poor

7

1554/ 1080

0.16 [0.02, 1.46]; P = 0.10

RE

I² = 99%; P < 0.00001

Postoperative complication

3

626/ 416

0.74 [0.36, 1.53]; P = 0.41

RE

I² = 54%; P = 0.12