2) gender
0 = female
1 = male

3) Education Level
1 = high school
2 = university

4) Years of Experience
1 = 0-1 year
2 = 1-3 year
3 = 5 + years
4 = 3-5 year

5) Daily Working Hours
1 = 8 + hours
2 = 6-8 hours

6) Do you feel stressed in your working environment?
0 = no
1 = yes

7) How many hours do you actively use your voice daily?
1 = 1-3 hours
2 = 5 +hours
3 = 3-5 hours

8) How would you describe your water intake habits?
1 = 0-1 liter
2 = 1-2 liters
3 = 2-3 liters
4 = 3 + liters

How is your voice today?
0 = normal
1 = Mildly impaired
2 = Moderately impaired

How would you describe your speaking voice use?
1 = I speak very little
2 = I speak normally
3 = I speak a lot

How would you describe your singing voice use?
1 = I never sing
2 = I sing occasionally
3 = I sing very frequently