Table 4.

Unadjusted and adjusted OR and 95% CI of knee pain by socioeconomic factors

	Unadjusted OR	Adjusted OR
Associated factor	Model 1	Model 2	Model 3
Gender
Male (Ref)
Female	1.03 (0.89 to 1.18)	1.23 (1.04 to 1.45)	0.69 (0.44 to 1.11)
Ethnicity
Malay (Ref)
Chinese	0.55 (0.47 to 0.64)	0.51 (0.43 to 0.61)	0.31 (0.14 to 0.68)
Indian	1.45 (1.17 to 1.81)	1.42 (1.12 to 1.78)	1.46 (0.55 to 3.91)
Age (years)
≤30 (Ref)
31–40	1.41 (1.14 to 1.75)	1.19 (0.94 to 1.51)	1.10 (0.69 to 1.75)
>40	1.76 (1.43 to 2.18)	1.60 (1.26 to 2.02)	1.26 (0.81 to 1.96)
Residence
Urban (Ref)
Rural	0.79 (0.69 to 0.91)	0.99 (0.85 to 1.16)	0.92 (0.76 to 1.12)
Education
Tertiary (Ref)
Secondary	1.26 (1.02 to 1.55)	1.37 (1.07 to 1.75)	1.47 (1.03 to 2.11)
Primary or non-formal	1.23 (1.05 to 1.43)	1.23 (1.04 to 1.45)	1.33 (1.07 to 1.66)
Employment status
No (Ref)
Yes	1.06 (0.91 to 1.23)	0.99 (0.83 to 1.18)	0.87 (0.68 to 1.11)
Ethnicity×gender
Chinese×female	–	–	1.22 (0.83 to 1.79)
Indian×female	–	–	2.09 (1.21 to 3.60)
Gender×age group
Female×age group (31–40)	–	–	1.24 (0.75 to 2.07)
Female×age group (>40)	–	–	1.96 (1.21 to 3.17)

Model 1: adjusted for other factors shown in the table.

Model 2: adjusted for other factors.

Model 3: adjusted for all possible two-way interactions terms with ethnicity. Only interaction terms that were significant are presented.