Table 2. Pooled hazard ratios for overall survival and recurrence-free survival.

Pooled analysis	Study number	HR (95% CI)	P for difference	P for heterogeneity and I-squared
Overall survival
All groups	7	0.84 (0.74 to 0.96)	0.013	0.063 and 49.8%
Excluding Cummings’s study	6	0.77 (0.61 to 0.97)	0.024	0.087 and 48.0%
In prospective studies	3	0.67 (0.37 to 1.20)	0.181	0.041 and 68.6%
In retrospective studies	4	0.86 (0.75 to 0.97)	0.019	0.137 and 45.7%
In colorectal Cancer	5	0.65 (0.43 to 0.99)	0.045	0.038 and 60.6%
Recurrence-free survival
All groups	11	0.88 (0.64 to 1.22)	0.457	<0.001 and 88.6%
Excluding Cummings’s study	10	0.83 (0.52 to 1.31)	0.424	<0.001 and 89.8%
In prospective studies	2	0.98 (0.79 to 1.20)	0.817	0.388 and 0.0%
In retrospective studies	9	0.81 (0.53 to 1.26)	0.353	<0.001 and 90.8%
In colorectal cancer	3	1.06 (0.97 to 1.16)	0.217	0.266 and 24.5%
In prostate cancer	3	0.62 (0.32 to 1.20)	0.153	0.036 and 69.9%