Table 1

Characteristics of the Cohort, China Health and Retirement Longitudinal Study, 2011–2012

	Total % (N=17 708)	Physical examination participants % (N=13 610)	Blood samples test participants % (N=11 546)
Age (years)
<50	24.42	23.05	22.84
50–59	35.90	36.16	36.58
≥60	39.68	40.79	40.59
Sex
Male	47.88	46.89	46.49
Female	52.12	53.10	53.50
Education
No formal education	27.21	28.34	28.75
Primary education	39.38	40.77	40.51
Secondary education and above	33.41	30.89	30.74
Hospital admission
Yes	9.06	8.77	9.06
No	90.94	91.23	90.94
Economic status
<1000	13.55	14.40	13.54
¥1000–4999	35.83	37.77	37.02
≥5000	42.51	41.62	42.99
Not clear	8.11	6.22	6.45
Community type
City	15.41	11.87	11.60
Others	28.60	28.78	28.55
Village	55.99	59.35	59.86