Table 2.

Variable assignment of covariates.

Variables	Variable assignment
Individual characteristics
Hukou status	1 = rural hukou 0 = urban hukou
Age	the actual age of the samples
Gender	1 = male 0 = female
Marital status	1 = married 0 = unmarried
Highest education	0 = illiterate/semi-literate category 1 = primary education 2 = junior secondary education 3 = senior secondary education 4 = higher education
Annual income	the actual annual income of samples with log-transformed
Selection of medical and health services
Hospitalization	1 = yes 0 = no
Medical expenditure	actual medical expenditure of samples with log-transformed
Hospital scale	1 = general hospital 2 = specialist hospital 3 = community healthcare center/township hospital 4 = community healthcare clinic/village clinic 5 = clinic
Clinic satisfaction	1 = excellent 2 = very good 3 = good 4 = poor 5 = disappointed
Hospital quality	1 = excellent 2 = very good 3 = good 4 = poor 5 = disappointed
Health behavior
Smoke	1 = yes 0 = no
Drink	1 = yes 0 = no
Nap	1 = yes 0 = no