Table 2.

Subgroup analysis of red meat and processed meat

Meat type	Pooled effect (RR, 95% CI)	P for heterogeneity	No. of studies
total red meat	1.44 (1.29, 1.61)	p = 0.000	28
By meat type
Red meat	1.55 (1.35, 1.77)	p = 0.000	24
Beef	1.39 (1.14, 1.69)	p = 0.433	6
Lamb	1.25 (0.97, 1.61)	p = 0.489	4
Pork	1.10 (0.70, 1.73)	p = 0.001	5
By study type
Cohort studies	1.21 (1.14, 1.28)	p = 0.712	6
Population-based CC	1.70 (1.36, 2.11)	p = 0.001	9
Hospital-based CC	1.37 (1.10, 1.72)	p = 0.000	15
By areas
The US	1.30 (1.17, 1.44)	p = 0.057	8
Europe	1.30 (1.05, 1.61)	p = 0.002	9
Asia	2.16 (0.76, 6.19)	p = 0.000	4
Uruguay	1.58 (1.34, 1.86)	p = 0.089	4
Canada	1.30 (1.12, 1.52)	p = 0.838	2
By genders
Both	1.54 (1.30, 1.83)	p = 0.000	14
Men	1.21 (0.94, 1.55)	p = 0.000	6
Women	1.39 (1.17, 1.65)	p = 0.018	12
Total processed meat	1.23 (1.10, 1.37)	p = 0.000	23
By meat type
processed meat	1.17 (1.06, 1.30)	p = 0.000	15
Bacon	1.67 (1.09, 2.56)	p = 0.016	4
Preserved meat	0.50 (0.35, 0.71)	p = .?	1
Salted meat	1.61 (0.87, 2.99)	p = 0.001	3
Sausage	1.33 (0.91, 1.94)	p = 0.008	5
By study type
Cohort studies	1.09 (0.99, 1.19)	p = 0.095	5
Population-based CC	1.46 (1.08, 1.97)	p = 0.000	8
Hospital-based CC	1.23 (1.01, 1.49)	p = 0.000	8
By areas
The United States	1.29 (1.09, 1.53)	p = 0.000	6
Europe	1.13 (0.78, 1.63)	p = 0.006	3
Asia	0.89 (0.56, 1.42)	p = 0.000	2
Uruguay	1.27 (1.00, 1.60)	p = 0.000	7
Canada	1.46 (1.24, 1.71)	p = 0.601	3
By genders
Both	1.11 (0.96, 1.28)	p = 0.000	12
Men	1.95 (1.34, 2.84)	p = 0.000	5
Women	1.09 (0.94, 1.28)	p = 0.172	6
By cancer type
Adenocarcinoma	1.19 (0.92, 1.54)	p = 0.002	6
Large cell carcinoma	1.31 (0.95, 1.80)	p = 0.400	3
Small cell	1.31 (0.97, 1.77)	p = 0.131	5
Squamous carcinoma	1.31 (0.97, 1.78)	p = 0.020	6