Use natural cleaning alternatives (e.g. lemon juice, vinegar, salt)
1 = Strongly disagree
2 = Disagree
3 = Neither agree nor disagree
4 = Agree
5 = Strongly agree

Gender
1 = Male
2 = Female

Marital status
1 = Single
2 = Married/living together
3 = Other

Age (in years, level)
1 = <=25
2 = 26-35
3 = 36-45
4 = 46-55
5 = >=56

Income in levels
1 = Low (under 30000 euros)
2 = Medium (from 30000 to 60000 Euros)
3 = High (0ver 60000 Euros)

Educational attainment
1 = High school or lower
2 = Vocational qualification
3 = College Graduate
4 = Master or doctoral degree

1 = Lower
2 = Medium
3 = Higher