Table 1.
Demographic and behavioral characteristics of the study sample by income group.
| Characteristics | High Income (n = 3752) | Medium Income (n = 3963) | Low Income (n = 3998) | P-value from Chi-2 test |
|---|---|---|---|---|
| CVD (%) | 12.21 | 13.18 | 13.81 | 0.100 |
| Hypertension (%) | 34.67 | 36.29 | 40.70 | <0.001 |
| Education | <0.001 | |||
| No formal education (%) | 19.35 | 27.00 | 37.74 | |
| No formal education but can read/write (%) | 14.82 | 19.58 | 21.79 | |
| Elementary school (%) | 21.35 | 23.72 | 21.74 | |
| Primary school and above (%) | 44.48 | 29.70 | 18.73 | |
| Employment status | <0.001 | |||
| Unemployed (%) | 16.70 | 14.68 | 22.43 | |
| Retired (%) | 13.47 | 10.07 | 8.46 | |
| Self-employed and farmers (%) | 47.01 | 60.59 | 63.48 | |
| Wage-earner (%) | 22.81 | 14.66 | 5.63 | |
| Urban residing (%) | 49.87 | 33.81 | 23.41 | 0.001 |
| Age# (year) | 57.28 (9.02) |
58.51 (8.82) |
61.97 (9.57) |
<0.001 |
| Male (%) | 47.44 | 47.56 | 46.82 | 0.778 |
| Unmarried (%) | 7.46 | 11.05 | 17.83 | 0.001 |
| HSI | <0.001 | |||
| Non-smokers (%) | 65.44 | 66.38 | 68.57 | |
| Low HSI (%) | 11.80 | 12.73 | 12.08 | |
| Medial/high HSI (%) | 22.76 | 20.89 | 19.35 | |
| Heavy drinking (%) | 14.39 | 14.26 | 13.86 | 0.779 |
| Irregular meals# | 11.57 | 15.92 | 16.76 | <0.001 |
| Naptime | <0.001 | |||
| <10 min (%) | 52.50 | 54.32 | 55.26 | |
| [10–60 min] (%) | 33.40 | 31.77 | 28.81 | |
| 60 min and over (%) | 14.10 | 13.90 | 15.93 | |
| Over-weight (%) | 35.42 | 30.43 | 27.89 | <0.001 |
Descriptive statistics of the study sample in CHARLS 2013.
#Mean, SD (numbers in the parentheses indicate SD); Cardiovascular diseases: CVD; HSI: the Heaviness of Smoking Index.