Table 1.

Basic characteristics of people with knee osteoarthritis in Beijing, China, 2008–2017.

Characteristics	Overall (n = 2,447,990)	Men (n = 984,823)	Women (n = 1,463,167)	p-Value ‡
Level of hospital, %
Primary	21	22	21	<0.001
Secondary	27	28	26
Tertiary	52	50	53
Age group *, %
18–34 years	9	8	11	<0.001
35–44 years	12	11	13
45–54 years	21	17	24
55–64 years	28	29	27
65–74 years	17	20	14
65–84 years	11	13	9
≥85 years	2	2	2
Area, %
Urban	76	73	78	<0.001
Rural	24	27	22
Working state, %
On work	42	47	38	<0.001
Retired	58	53	62

Note: * Age group by age at diagnosis; ^‡ p-value for sex differences in the characteristics of people with knee osteoarthritis.