Table 1 Trial characteristics

Year of publication

2001–2010

4(6.45%)

15.13 ± 3.45

0.934

0.354

2011–2022

58(93.54%)

13.85 ± 2.58

Region in which trials were conducted

Asia

26(41.93%)

13.85 ± 2.34

-1.413

0.163

Europe and North America

36(58.06%)

14.33 ± 2.79

Sources of trial funding

Government/foundation

10(16.13%)

15.00 ± 3.09

2.948

0.040

Government and industry

5(8.06%)

14.70 ± 2.28

Completely funded by industry

29(46.77%)

13.95 ± 2.73

Funding not reported

18(29.03%)

12.28 ± 2.14

Journal impact factor

< 4

20(32.26%)

12.58 ± 2.17

20.418

< 0.01

4–10

14(22.58%)

12.21 ± 2.32

> 10

28(45.16%)

15.77 ± 2.63

The control group interventions

Warfarin

37(59.68%)

14.07 ± 2.62

0.478

0.634

Others

25(40.32%)

13.74 ± 2.69

Sample size

< 200

22(35.48%)

12.57 ± 2.22

7.127

< 0.01

200–400

9(14.52%)

13.61 ± 2.06

> 400

31(50%)

13.94 ± 2.63

International collaboration

Yes

27(43.55%)

14.83 ± 2.71

2.457

0.017

No

35(56.45%)

13.24 ± 2.38