Table 2

Adjusted^2-150 odds ratio (with 95% confidence interval (CI)) of rheumatoid factor (RF) positivity (sensitised sheep cell agglutination titre ⩾128) for different factors

Factor	Unit or category	Number of subjects examined	Number of RF positive cases	Odds ratio	95% CI	p Value^2-151
Consumption of coffee	For each SD, 2.8 cups	6809	69	1.24	0.97 to 1.58	0.09
Age	For each SD, 14.1 years	6809	69	1.41	1.09 to 1.83	0.01
Sex		Men	3132	37	1.00
Sex		Women	3677	32	1.31	0.75 to 2.28	0.34
Serum LDL cholesterol^2-152	For each SD, 1.2 mmol/l	6809	69	1.28	1.04 to 1.59	0.03
Smoking		Never smoked	3789	21	1.00
		Quit	1414	18	2.78	1.36 to 5.69
		Cigars, pipe or					0.0003
		<20 Cigarettes/day	1004	20	4.32	2.19 to 8.54
		⩾20 Cigarettes/day	602	10	3.77	1.57 to 9.04

↵2-150 All variables in the table were included in the logistic regression model.
↵2-151 Likelihood ratio test for linear trend (continuous variables) or for heterogeneity (groups of categorised variables).
↵2-152 LDL cholesterol = low density lipoprotein cholesterol.