Comparison 7. Sensitivity analysis: inclusion of missing data, assuming loss to follow‐up developed incisional hernia.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Absorbable versus non‐absorbable (hernia)	16	5610	Risk Ratio (M‐H, Random, 95% CI)	1.11 [0.94, 1.30]
1.1 Same closure technique and method in each group	14	5257	Risk Ratio (M‐H, Random, 95% CI)	1.06 [0.96, 1.17]
1.2 Different closure technique or method in each group	2	353	Risk Ratio (M‐H, Random, 95% CI)	1.24 [0.21, 7.21]
2 Mass versus layered closure (hernia)	5	1220	Risk Ratio (M‐H, Random, 95% CI)	1.82 [0.81, 4.10]
2.1 Same closure technique and suture material in each group	1	206	Risk Ratio (M‐H, Random, 95% CI)	3.86 [1.34, 11.07]
2.2 Different closure technique or suture material in each group	4	1014	Risk Ratio (M‐H, Random, 95% CI)	1.40 [0.50, 3.94]
3 Continuous versus interrupted	11	4046	Risk Ratio (M‐H, Random, 95% CI)	0.89 [0.61, 1.30]
3.1 Same closure method and suture material in each group	4	1363	Risk Ratio (M‐H, Random, 95% CI)	1.13 [0.94, 1.35]
3.2 Different closure method or suture material in each group	7	2683	Risk Ratio (M‐H, Random, 95% CI)	0.81 [0.45, 1.44]
4 Monofilament versus multifilament (hernia)	16	4981	Risk Ratio (M‐H, Random, 95% CI)	0.77 [0.63, 0.95]
4.1 Same closure technique and method	10	2982	Risk Ratio (M‐H, Random, 95% CI)	0.87 [0.72, 1.05]
4.2 Different closure technique or method	6	1999	Risk Ratio (M‐H, Random, 95% CI)	0.64 [0.42, 0.98]
5 Slow absorbable versus fast absorbable (hernia)	9	3877	Risk Ratio (M‐H, Random, 95% CI)	0.89 [0.74, 1.07]
5.1 Same closure method and technique	5	1863	Risk Ratio (M‐H, Random, 95% CI)	0.95 [0.77, 1.17]
5.2 Different closure method or technique	4	2014	Risk Ratio (M‐H, Random, 95% CI)	0.79 [0.56, 1.12]