Table 4.

Concurrent validity of the COHL (N = 370)

	Mean (SD)	P*
Age (years)
18–44	18.5 ± 5.0	< 0.001
45–64	16.1 ± 5.2
65–80	14.5 ± 4.7
Educational level
Less than primary school	11.2 ± 4.5	< 0.001
Junior high school	10.7 ± 4.1
Senior high school or technical secondary school	14.2 ± 5.1
Junior college	16.5 ± 4.8
College/university diploma or higher	18.4 ± 4.0
Monthly income (RMB yuan)
< 2000	14.0 ± 5.9	0.004
< 4000	16.0 ± 5.1
< 6000	16.6 ± 5.2
< 8000	16.7 ± 4.5
< 10,000	17.8 ± 4.5
≥ 10,000	18. 4 ± 3.9
Oral condition self-assessment
Good	18.2 ± 5.0	0.013
Moderate	17.0 ± 4.7
Poor	15.9 ± 4.5

SD standard deviation

*Obtained from Kruskal–Wallis test