Table 1.

Demographic characteristic of participants

	Demographics	n	Percentage (%)
Sex	Female	557	15.8
	Male	2,960	84.2
Education	Senior high school or below	760	21.6
	Academy	1,207	34.3
	Bachelor’s or above	1,550	44.1
Marital status	Married	2,769	78.7
	Unmarried	692	19.7
	Others	56	1.6
Location	Yijiang district	334	9.5
	Wuhu county	467	13.3
	Sanshan district	169	4.8
	Nanling county	387	11
	Jiujiang district	460	13.1
	Jinghu district	645	18.3
	Jingkai district	97	2.8
	Fanchang county	360	10.2
	Wuwei county	598	17
Police classification	Criminal	330	9.4
	Security	942	26.8
	Regimental	341	9.7
	Traffic	727	20.7
	Command center and logistics support	205	5.8
	Organizational, internal, and political security	198	5.6
	Prison guards	93	2.6
	Auxiliary	681	19.4
Use of sleeping pills	No	3,401	96.7
	Yes	116	3.3