Factor

Frequency

Percentage

Year of the study

2000-2005

17

38

2006-2010

11

24

2011-2016

17

38

Type of study

Cohort

32

73

Cross-sectional

8

18

RCTs

3

7

Case-control

1

2

Countries of the study

Asia Pacific

37

82

Pacific region

5

11

United states

3

7

Gender of participants

Male and female

15

33.3

Male

2

4.5

Female

9

20

Unknown

19

42.2