Table 2.

Sensitivity analyses

Strata of analysis for each outcome	Number of studies included	HR (95% CI); P-value	Heterogeneity
A. Studies with definition for cancer specific mortality included [6,9,19,20,51,52,54,55,58,60]	10	1.49 (1.29 to 1.72); P <0.001	I2:23.4%; P = 0.23
B. Only Stage III/IV colorectal carcinoma studies included [6,24,51,52]	High versus Low: 2	High versus Low: 1.64 (1.34 to 2.00); P <0.001	I2: 0%; P = 0.38
	Positive versus Negative: 2	Positive versus Negative: 1.95 (1.32 to 2.87); P = 0.001	I2: 46.7%; P = 0.17
	Overall colorectal studies: 4	Overall colorectal studies: 1.70 (1.42 to 2.03); P <0.001	I2: 7.2%; P = 0.36