Number of allergens
Before the COVID-19 (n=12484) n (%) After the COVID-19 (n=17422) n (%)
X2
P
0 10648(85.3) 11331(65.0) 1621.815 <0.001
1 1060(8.5) 3137(18.0)
2 707(5.7) 2227(12.8)
3 49(0.4) 526(3.0)
4 12(0.1) 139(0.8)
>4 8(0.1) 82(0.5)