Three RCTs were included (128 participants, range 20 to 54). All trials were described as being of good quality (Delphi scores of 7). The authors reported that the groups appeared similar at baseline, that all studies made use of consecutive sealed envelopes and that all used an intention-to-treat analysis. None of the studies clearly described blinding techniques and timing of randomisation. Follow-up ranged from 12 to 83 months.
Fewer patients in the mesh group developed a parastomal hernia compared with the control group and the difference was statistically significant (RR 0.25, 95% CI 0.13 to 0.48; three RCTs; Ι²=36%).