The relationship remained significant concerning education and self-reported diagnosis of arthritis in subgroup analysis for females ( P = 0.0143) but failed to reach statistical significance for males ( P = 0.7210).
The overall relationship remained significant in adjusted overall logistic regression comparing for self-reported diagnosis of arthritis for 2-5 hours of sleep (with 6-7 hours of sleep as the reference) (odds ratio: 1.35 [95% CI: 1.08, 1.70; P = 0.0103]); however, when the data were stratified by sex, the association failed to reach significance.