Table 4.

Summary of comparison between chronic low back and knee pain^a in relation to correlating factors of adjusted ORs

Correlating factors	Low back pain	Knee pain
Sex	OR for women was 0.85 (95% CI 0.75–0.97)	OR for women was 1.27 (95% CI 1.09–1.49)
Age	No significant association in men OR for subjects aged ≥70 years was 1.94 (95% CI 1.35–2.70) with reference to those aged <50 years in women	Robust positive associations with ORs in men and women (Ptrend<0.0001)
Education level	Significant inverse association with ORs (Ptrend=0.0003) in men No significant association in women	Significant inverse associations with ORs in men and women (Ptrend=0.0008 and 0.0027, respectively)
Household income	Significant inverse association with ORs (Ptrend<0.0001) in men No significant association in women	No significant associations in men and women
Occupation	OR for manual was 1.45 (95% CI 1.08–1.95) with the reference group in men No significant association in women	No significant associations in men and women
BMI	No significant association in men Weak positive association with ORs in women (Ptrend=0.0175)	Robust positive associations with ORs in men and women (Ptrend<0.0001)

Notes: ORs adjusted for all other variables.

^aModerate, severe, or very severe chronic pain as outcome.

Abbreviation: BMI, body mass index.