Table A1.

Baseline characteristics of the observations.

Variables	Category	Jingmen		Other Cities
		Mean/Frequency	Sta. Dev./Percentage	Mean/Frequency	Sta. Dev./Percentage
Age	-	59.6	8.6	61.4	9.4
Sex	Male	41	48.8	6059	47.7
	Female	43	51.2	6644	52.3
Marital status	Married	72	85.7	10,995	86.5
	Unmarried *	12	14.3	1708	13.5
Education	Illiterate	8	9.5	3219	25.3
	Below elementary school	19	22.6	2651	20.9
	Elementary	16	19.1	2727	21.5
	Junior high school	22	26.2	2645	20.8
	High school or above	19	22.6	1461	11.5
Self-rated health	Good	5	6.0	1434	11.3
	Fair	64	76.1	7845	61.7
	Poor	15	17.9	3424	27.0
Type of Hukou	Rural	40	47.6	10,200	80.3
	Urban	44	52.4	2503	19.7
Per capita income	-	10,016.1	14,415.9	11,758.6	72,608.4
Number of chronic diseases	0	30	35.7	3235	25.5
	1	22	26.2	3425	27.0
	2	13	15.5	2652	20.8
	$\ge$3	19	22.6	3391	26.7
Sample size	-	84		12,703

Note *: the unmarried includes the following: separated, divorced, widowed and unmarried.