Table 4.

Knowledge about factors that may influence the risk for COVID-19 infection among the three studied groups (n = 277).

%(n)	MS patients (n = 115)	MS caregivers (n = 33)	Controls (n = 129)	Test of significance p-value
Knowledge about factors that may influence the risk for COVID-19				Chi Square test
Age of the individual				X2=3.236 P = 0.779
Not at all	5.2(6)	3.0(1)	4.7(6)
To little extent	18.3(21)	27.3(9)	18.6(24)
To great extent	71.3(82)	69.7(23)	72.9(94)
Don't know	5.2(6)	0.0(0)	3.9(5)
Smoking				X2=17.734 P = 0.007*
Not at all	3.5(4)	0.0(0)	1.6(2)
To little extent	19.1(22)	12.1(4)	12.4(16)
To great extent	50.4(58)	72.7(24)	74.4(96)
Don't know	27.0(31)	15.2(5)	11.6(15)
Psychological state				X2=11.186 P = 0.083
Not at all	4.3(5)	15.2(5)	7.0(9)
To little extent	27.0(31)	36.4(12)	37.2(48)
To great extent	56.5(65)	45.5(15)	49.6(64)
Don't know	12.2(14)	3.0(1)	6.2(8)
Adequate sleep				X2=10.176 P = 0.115
Not at all	11.3(13)	15.2(5)	9.3(12)
To little extent	30.4(35)	39.4(13)	45.7(59)
To great extent	36.5(42)	30.3(10)	34.9(45)
Don't know	21.7(25)	15.2(5)	10.1(13)
Physical exercise				X2=17.270 P = 0.008*
Not at all	18.3(21)	18.2(6)	9.3(12)
To little extent	33.9(39)	45.5(15)	41.9(54)
To great extent	18.3(21)	18.2(6)	33.3(43)
Don't know	29.6(34)	18.2(6)	15.5(20)
Certain foods/drinks				X2=16.752 P = 0.010*
Not at all	12.2(14)	12.1(4)	18.6(24)
To little extent	31.3(36)	33.3(11)	46.5(60)
To great extent	27.0(31)	36.4(12)	22.5(29)
Don't know	29.6(34)	18.2(6)	12.4(16)
Taking vitamins				X2=18.550 P = 0.005*
Not at all	0.9(1)	9.1(3)	6.2(8)
To little extent	23.5(27)	27.3(9)	40.3(52)
To great extent	63.5(73)	51.5(17)	48.8(63)
Don't know	12.2(14)	12.1(4)	4.7(6)
Vitamin A	10.4(12)	6.1(2)	4.7(6)	X2=3.055 P = 0.217
Vitamin B	13.9(16)	18.2(6)	3.1(4)	X2=11.634 P = 0.003*
Vitamin C	64.3(74)	60.6(20)	65.6(128)	X2=0.290 P = 0.865
Vitamin D	33.9(39)	24.2(8)	10.9(14)	X2=18.673 P=<0.001*
Vitamin E	7.0(8)	6.1(2)	2.3(3)	X2=3.024 P = 0.220

^⁎Significant at (P ≤ 0.05).