Table 1.

The definition and abbreviation of selected variables in the study.

Variable	Abbreviation	Definition
Smoking index	SI	Categorical variable scored 1 if 0 < SI < 400, 2 if SI≥400, and 0 if respondents were never smokers.
Outpatient service utilization	Outpatient	Binary variable scored 1 if respondents had outpatient visits in the past year and 0 otherwise
Number of outpatient visits ≥3	-	Binary variable scored 1 if respondents had outpatient visits ≥3 times in the past year and 0 if respondents had an outpatient visit
Inpatient service utilization	Inpatient	Binary variable scored 1 if respondents had hospital admissions in the past year and 0 otherwise
Number of times hospitalized ≥2	-	Binary variable scored 1 if respondents had hospital admissions ≥2 times in the past year and 0 if respondents had a hospital admission
Age	Age	Continuous variable measured in years
Gender	Gender	Binary variable scored 1 for males and 0 for females
Educational level	Education	Categorical variable scored 1 for Illiterate, 2 for Primary School, 3 for Middle School, 4 for High School and Junior College, and 5 for College and above
Marital status	Marriage	Categorical variable scored 1 for Single, 2 for Married, and 3 for Divorced or Widowed
Logarithm of family income	Lnincome	Continuous variable
Residence location	Residence	Binary variable scored 1 for rural and 2 for urban
Work status	Work	Binary variable scored 1 for employed people, 0 for Unemployed people
Health insurance	Insurance	Binary variable scored 1 for insurance covered, 0 for no insurance covered
Health status	Health status	Binary variable scored 1 for at least one chronic disease, 0 for no chronic diseases.
Drink	Drink	Binary variable scored 1 if respondents had drinking habits and 0 otherwise
Whether the increase in the price of cigarettes reduced smoking	PRS	Binary variable scored 1 if the increase in cigarette prices reduced the number of cigarettes smoked and 0 otherwise