Table 2 Bivariate analysis of variables associated with risk of Multiple Sclerosis

 First child in family, yes/no

2.02

 Family history of MS, yes/no

5.16

 Sun exposure during primary school, high/low

0.55

 Sun exposure during intermediate school, high/low

0.54

 Sun exposure during secondary school, high/low

0.45

 Sun exposure during university school, high/low^a

0.33

 Breastfeeding, yes/no^b

 ≥ 5 Servings of fruits / week, yes/no

0.30

 ≥ 5 Servings of vegetables / week, yes/no

0.57

 ≥ 5 dates times / week, yes/no

0.94

 ≥ 5 red meat times / week, yes/no

0.97

 ≥ 5 milk times / week, yes/no

1.32

 ≥ 5 Fast food times/week, yes/no

3.21

 ≥ 5 Dairy products times / week, yes/no

1.42

 Daily coffee intake, yes/no

0.53

 History of measles infection, yes/no

3.05

 History of chicken pox infection, yes/no

0.90

 Appendectomy, yes/no

0.72

 Tonsillectomy, yes/no

1.25

 Type I diabetes mellitus, yes/no

0.67

 Migraine, yes/no

0.91

 Systematic lupus erythematosus, yes/no

0.19

 Rheumatoid arthritis, yes/no

0.94

 Thyroid disorder, yes/no

0.55

 Crohn’s disease, yes/no

1

 Ulcerative colitis, yes/no

1.41

 Psoriasis, yes/no

1.77

 Type I diabetes mellitus, yes/no

1.01

 Migraine, yes/no

0.90

 Systematic lupus erythematosus, yes/no

0.61

 Rheumatoid arthritis, yes/no

1.02

 ≥ 13-year age of menarche, yes/no

1.11

 Current tobacco use, cases/controls

1.16

 Ex-smoker, cases/controls

1.32

 Never smoker, cases/controls

Ref.

 Passive smoking in childhood, yes/no

1

 ≥ 30, cases/controls

0.92

 25–29.99, cases/controls

0.75

 ≤ 24.99, cases/controls

Ref.

 Parental consanguinity (first cousin), yes/no

0.67