Table 1 Descriptive characteristics of respondents in CHARLS study
year | 2011 | 2013 | 2015 |
|---|---|---|---|
total residents, n | 8357 | 6053 | 8268 |
age, n (%) | |||
 45–54 | 32.68 | 34.63 | 30.95 |
 55–64 | 38.64 | 36.40 | 34.83 |
 65–74 | 20.26 | 21.99 | 25.48 |
  > =75 | 8.42 | 6.99 | 8.73 |
gender, n (%) | |||
 male | 48.07 | 35.65 | 47.80 |
 female | 51.93 | 64.35 | 52.20 |
education level, n (%) | |||
 no formal education | 27.01 | 27.36 | 23.43 |
 elementary school | 61.86 | 61.72 | 64.71 |
 middle/high school | 9.76 | 9.28 | 9.99 |
 college degree or higher | 1.36 | 1.64 | 1.87 |
origin, n (%) | |||
 urban | 35.83 | 35.29 | 36.02 |
 rural | 64.17 | 64.71 | 63.98 |
insurance status, n (%) | |||
 no insurance | 6.55 | 3.67 | 10.28 |
 basic medical insurance | 92.45 | 95.80 | 85.63 |
 other types | 1.01 | 0.53 | 4.09 |
smoking status, n (%) | |||
 yes | 31.24 | 18.16 | 29.70 |
 no or abstained from smoking | 68.76 | 81.84 | 70.30 |
drinking status, n (%) | |||
 yes | 25.67 | 21.76 | 27.54 |
 no or abstained from drinking | 74.33 | 78.24 | 72.46 |
BMI, n (%) | |||
 low weight | 6.62 | 5.01 | 5.31 |
 normal | 62.67 | 56.22 | 59.40 |
 overweight | 25.79 | 31.95 | 29.96 |
 obesity | 4.93 | 6.82 | 5.33 |