Number

Percent

Gender

Male

20

24.7

Female

61

75.3

Age (years)

Mean ± SD

23.5 ± 2.3

Marital status

Single

74

91.3

Married

7

8.7

Sources of opinion and knowledge

Personal observation

52

64.2

Mass media

10

12.3

Newspapers and books

14

17.3

Professional publication

15

18.5

Explanation from a professional

51

63

Lecture in school

65

80.2

Others

4

4.9