In Figure 17.24: (a) the squares represent the observed treatment ratios for the trials; (b) the areas of the squares depend on the weight given to each study; (c) studies with long horizontal lines...

In Figure 17.24:

(a) the squares represent the observed treatment ratios for the trials;

(b) the areas of the squares depend on the weight given to each study;

(c) studies with long horizontal lines should be given most weight in the meta-analysis;

(d) there is clear evidence of a relationship between the intervention and surgical site infection;

(e) none of the individual trials was big enough to detect the difference which might exist between these two treatments.