Table 2.

Association between caffeine intake and constipation

Caffeine intake	Number	Crude model		Adjusted model
		OR (95% CI)	P	OR (95% CI)	P
Q1	3204	Ref		Ref
Q2	3098	1.11 (0.93–1.32)	0.252	0.99 (0.82–1.21)	0.954
Q3	2859	0.62 (0.50–0.76)	< 0.001	0.60 (0.49–0.74)	< 0.001
Q4	2453	0.72 (0.55–0.93)	0.011	0.77 (0.59–0.99)	0.047
Q5	2202	0.65 (0.51–0.83)	< 0.001	0.72 (0.56–0.92)	0.009

Abbreviation: OR, odds ratio; CI, confidence interval

Crude model: weighted univariate logistic regression analysis

Adjusted model: weighted multivariable logistic regression analysis adjusted age, gender, PIR, drinking, depression, BMI, dietary fiber, and moisture