Table 4 Pooled outcomes of subgroup analysis for studies with comparable tumor size or risk index

Operation time (min)

13

371

377

<0.001, 81%

WMD = -1.06

-16.93, 14.81

0.90

Blood loss (ml)

11

300

302

<0.001, 71%

WMD = -58.20

-81.76, -34.65

<0.01

Time to first flatus (d)

6

129

142

0.09, 47%

WMD = -1.28

-1.60, -0.97

<0.01

Time to oral intake (d)

7

212

241

0.02, 61%

WMD = -1.77

-2.18, -1.35

<0.01

Hospital stay (d)

11

309

339

0.006, 60%

WMD = -2.87

-3.54, -2.21

<0.01

Overall complications

12

341

345

0.74, 0%

RR = 0.49

0.30, 0.81

<0.01

Tumor size (cm)

13

371

377

0.23, 21%

WMD = -0.57

-0.86, -0.29

<0.01

Recurrence

8

248

232

0.81, 0%

RR = 0.66

0.31, 1.42

0.29