Table 1.

Sociodemographic information of the participants

Variable		Number	Percentage (%)
Gender	Male	12,217	53.2
	Female	10,766	46.8
Place of origin	Urban	13,721	59.7
	Non-urban	9,262	40.3
Grade	Freshman	12,633	55.0
	Sophomore	5,789	25.2
	Junior year	2,651	11.5
	Senior year	794	3.5
	Fifth year of college	30	0.1
	Master	933	4.1
	Doctor	153	0.6
Whether an only child	Only son	12,077	52.5
	Non-only child	10,906	47.5
Whether you hold a position in the university	Student leaders (class/ student/society, etc.)	7,850	34.2
	No job	13,922	60.6
	Student leader in the past	1,211	5.2
Residential experience in middle and high school	Yes	13,469	58.6
	No	9,514	41.4
The highest level of education received by his or her parents	Primary school and below	1,434	6.2
	Junior high school	8,012	34.9
	High school or technical secondary school	7,048	30.7
	Junior college	2,526	11.0
	Undergraduate	3,476	15.1
	Master degree or above	487	2.1
Monthly living expenses(Yuan)	< 1,000	1,409	6.1
	1,000–1,500	9,755	42.4
	1,500–2,000	8,121	35.3
	2,500–3,000	2,655	11.6
	> 3,000	1,043	4.6
The pressure of study and life in the past two months	1-Extremely little stressed	2,177	9.5
	2-Very little stressed	4,217	18.3
	3-Little stressed	8,363	36.4
	4-Much stressed	6,122	26.6
	5-Very much stressed	1,497	6.5
	6-Extremely much stressed	607	2.7
The degree of interest in professional knowledge	Very interested	5,014	21.8
	Have interested	9,243	40.2
	Generally	5,216	22.7
	Less interest	3,019	13.1
	No interest	491	2.2
Weekly exercise time (hours)	1	12,709	55.3
	2	6,430	28.0
	3	2,152	9.4
	4	1,682	7.3
Smoking	Smoking	979	4.3
	Quit smoking	557	2.4
	Never smoked	21,447	93.3
Drinking	Drinking	5,569	24.2
	Quit drinking	986	4.3
	Never drank	16,428	71.5
Overall satisfaction with study	Very satisfied	3,569	15.5
	Satisfied	9,077	39.5
	Generally	8,823	38.4
	Dissatisfied	1,196	5.2
	Very dissatisfied	318	1.4
Sleep quality in the past two months	Very bad	431	1.9
	Pretty bad	1,696	7.4
	Generally	7,728	33.6
	Good	8,924	38.8
	Very good	4,204	18.3