Table 1.

Socio-demographic variables of this sample (N = 146,102).

Variables	N	%
Gender
Female	90,701	62.1
Male	55,401	37.9
Age(years)
16-18	8,163	5.6
19-21	93,713	64.1
22-24	39,012	26.7
≥25	5,214	3.6
Grade
Freshman	46,101	31.6
Sophomore	41,012	28.1
Junior	32,717	22.4
Senior	17,824	12.2
Postgraduate	8,448	5.8
Residence location
Rural	95,388	65.3
Urban	50,714	34.7
No. of siblings in the family
1	32,417	22.2
≥2	113,685	77.8
History of physical illness
Yes	476	0.3
No	145,626	99.7
History of mental illness
Yes	1,170	0.8
No	144,932	99.2
The severity of the COVID-19 in your areaθ
Severe	619	0.4
Moderate	133,031	91.1
Mild	12,452	8.5
Whether to return to school
Yes	9,518	6.5
No	136,584	93.5

Note: θThe severity of the COVID-19 in the area: Severe areas have more than 10,000 cumulative confirmed cases (e.g. Hubei province); moderate areas have 1,000 to 9,999 cumulative confirmed cases (e.g. Guangdong province), and the remaining provinces in China are mild areas with less than 1,000 cumulative confirmed cases (e.g. Sichuan province).