Comparison 1. Decompression alone versus decompression plus fusion.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Pain	4	446	Mean Difference (IV, Random, 95% CI)	1.09 [‐4.07, 6.26]
1.1 Short‐term (less than 12 months)	1	66	Mean Difference (IV, Random, 95% CI)	4.50 [‐0.70, 9.70]
1.2 Long‐term (12 months or more)	4	380	Mean Difference (IV, Random, 95% CI)	‐0.29 [‐7.32, 6.74]
2 Disability	3	401	Mean Difference (IV, Random, 95% CI)	3.37 [‐3.37, 10.11]
2.1 Short‐term (less than 12 months)	1	66	Mean Difference (IV, Random, 95% CI)	5.2 [‐3.50, 13.90]
2.2 Long‐term (12 months or more)	3	335	Mean Difference (IV, Random, 95% CI)	3.26 [‐6.12, 12.63]
3 Walking ability	3	316	Risk Ratio (IV, Random, 95% CI)	0.99 [0.79, 1.24]
3.1 Long‐term (12 months or more)	3	316	Risk Ratio (IV, Random, 95% CI)	0.99 [0.79, 1.24]
4 Operation time	4	381	Mean Difference (IV, Random, 95% CI)	‐107.94 [‐161.65, ‐54.23]
5 Blood loss	4	383	Mean Difference (IV, Random, 95% CI)	‐0.52 [‐0.70, ‐0.34]
6 Reoperations	5	443	Risk Ratio (IV, Random, 95% CI)	1.25 [0.81, 1.92]
7 Hospitalisation	2	295	Mean Difference (IV, Fixed, 95% CI)	‐1.69 [‐2.12, ‐1.26]