Table 2. Characteristics of case-control studies evaluating coffee consumption and colorectal cancer risk included in a meta-analysis.

	Study period	Sex	Coffee intake	OR (95% CI)	Reference category
Colon
Inoue et al30	1990–1995	Men and Women	Occasionally	0.83 (0.61, 1.14)	Rarely
			1–2 cups/day	0.97 (0.74, 1.27)
			>3 cups/day	0.87 (0.56, 1.35)
Wang et al31	2000–2003	Men and Women	1–3 cups/week	1.04 (0.69, 1.57)	<1 cup/week
			4–6 cups/week	0.75 (0.47, 1.18)
			1–3 cups/day	0.64 (0.47, 0.87)
			>4 cups/day	0.78 (0.53, 1.35)
Nakagawa et al19 HERPACC-I	1988–2000	Men	<1 cup/day	0.78 (0.55, 1.10)	None
			1–2 cups/day	0.82 (0.62, 1.09)
			>3 cups/day	0.97 (0.64, 1.46)
		Women	<1 cup/day	0.96 (0.68, 1.37)	None
			1–2 cups/day	0.91 (0.67, 1.25)
			>3 cups/day	0.63 (0.35, 1.13)
Nakagawa et al19 HERPACC-II	2001–2005	Men	<1 cup/day	0.60 (0.37, 0.97)	None
			1–2 cups/day	0.62 (0.38, 0.99)
			>3 cups/day	0.59 (0.33, 1.06)
		Women	<1 cup/day	1.18 (0.68, 2.04)	None
			1–2 cups/day	1.28 (0.76, 2.17)
			>3 cups/day	1.22 (0.59, 2.51)
Rectum
Inoue et al30	1990–1995	Men and Women	Occasionally	0.77 (0.53, 1.11)	Rarely
			1–2 cups/day	0.91 (0.67, 1.24)
			>3 cups/day	0.46 (0.26, 0.81)
Wang et al31	2000–2003	Men and Women	1–3 cups/week	0.63 (0.38, 1.04)	<1 cup/week
			4–6 cups/week	0.55 (0.32, 0.93)
			1–3 cups/day	0.63 (0.45, 0.88)
			>4 cups/day	0.82 (0.54, 1.23)
Nakagawa et al19 HERPACC-I	1988–2000	Men	<1 cup/day	0.84 (0.60, 1.17)	None
			1–2 cups/day	0.91 (0.69, 1.19)
			>3 cups/day	0.60 (0.41, 0.89)
		Women	<1 cup/day	1.18 (0.80, 1.74)	None
			1–2 cups/day	0.91 (0.64, 1.28)
			>3 cups/day	0.88 (0.48, 1.60)
Nakagawa et al19 HERPACC-II	2001–2005	Men	<1 cup/day	0.91 (0.55, 1.51)	None
			1–2 cups/day	1.06 (0.65, 1.73)
			>3 cups/day	0.98 (0.54, 1.78)
		Women	<1 cup/day	1.32 (0.69, 2.50)	None
			1–2 cups/day	0.94 (0.49, 1.24)
			>3 cups/day	0.91 (0.42, 2.02)

CI, confidence interval; OR, odds ratio.