Fig. 2.

a Meta-analysis of influence of surgical margin on disease free survival after hepatic resection of colorectal metastases: all 11studies. (Odds ratios were calculated using the random effects model. Large diamond at the bottom represents the overall effect of negative margins on the disease free survival. Small diamonds embedded in squares represent the individual study effects with 95 % confidence intervals represented by the horizontal bars). b Funnel plot for meta-analysis of 11 studies depicting one notably outlier study