Comparison 1. Surgery versus non‐surgery.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Mean BMI [kg/m2]			Other data	No numeric data
2 Mean BMI at study end	5		Mean Difference (IV, Random, 95% CI)	Totals not selected
3 BMI reduction			Other data	No numeric data
4 Weight [kg]			Other data	No numeric data
5 Mean weight at study end	4		Mean Difference (IV, Random, 95% CI)	Totals not selected
6 Weight loss [kg]			Other data	No numeric data
7 Weight loss at study end	3	260	Mean Difference (IV, Random, 95% CI)	21.27 [18.93, 23.61]
8 Initial weight loss [%]			Other data	No numeric data
9 Initial weight loss at study end	5		Mean Difference (IV, Random, 95% CI)	Totals not selected
10 Excess weight loss [%]			Other data	No numeric data
11 % excess weight loss at study end	2		Mean Difference (IV, Random, 95% CI)	Totals not selected
12 Other weight change data			Other data	No numeric data
13 Health‐related quality of life			Other data	No numeric data
14 Comorbitidies: diabetes			Other data	No numeric data
15 Comorbitidies: hypertension			Other data	No numeric data
16 Comorbitidies: metabolic syndrome			Other data	No numeric data
17 Comorbitidies: Lipids			Other data	No numeric data
18 Comorbitidies: Sleep			Other data	No numeric data