Table 1. Demographic characteristics of study participants.

Demographic characteristics	N (constituent ratio %)
Sex
Male	29 (63.04)
Female	17 (36.96)
Age (in years)
20–29	9 (19.56)
30–39	5 (10.87)
40–49	15 (32.61)
50–59	12 (26.09)
60–65	5 (10.87)
Ethnicity
Han	19 (41.30)
Zhuang	25 (54.35)
Yao	2 (4.35)
Education
Primary school or less	12 (26.09)
Junior high school or less	20 (43.48)
High school or higher	14 (30.43)
Marital status
Married	32 (69.56)
Unmarried	10 (21.74)
Divorced	2 (4.35)
Widowed	2 (4.35)
Profession
Farmer	17 (39.95)
Staff	10 (21.74)
Migrant laborer	10 (21.74)
Health personnel	2 (4.35)
Unemployed	5 (10.87)
Other	2 (4.35)
History of drug abuse
None	37 (80.44)
Ever	9 (19.56)