Comparison 1. surgery vs surgery + chemotherapy.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 survival	16	4457	Peto Odds Ratio (95% CI)	1.04 [0.96, 1.12]
1.1 long term alkylating agents	5	2145	Peto Odds Ratio (95% CI)	1.15 [1.04, 1.27]
1.2 other drugs	4	918	Peto Odds Ratio (95% CI)	0.89 [0.72, 1.11]
1.3 cisplatin based	8	1394	Peto Odds Ratio (95% CI)	0.87 [0.74, 1.02]
2 subgroup for survival ‐ age	4		Peto Odds Ratio (95% CI)	Totals not selected
3 subgroup for survival ‐ sex	2		Peto Odds Ratio (95% CI)	Totals not selected
4 subgroup for survival ‐ performance status	2		Peto Odds Ratio (95% CI)	Totals not selected
5 subgroup for survival ‐ histology	3		Peto Odds Ratio (95% CI)	Totals not selected
6 subgroup for survival ‐ stage	2		Peto Odds Ratio (95% CI)	Totals not selected