Comparison 3. Beta‐blockers vs control: subgroup by start of beta‐blocker therapy.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Early all‐cause mortality	16	11446	Risk Ratio (M‐H, Random, 95% CI)	1.17 [0.89, 1.54]
1.1 Before surgery	7	10135	Risk Ratio (M‐H, Random, 95% CI)	1.17 [0.83, 1.64]
1.2 During surgery	6	797	Risk Ratio (M‐H, Random, 95% CI)	0.56 [0.18, 1.69]
1.3 After surgery	3	514	Risk Ratio (M‐H, Random, 95% CI)	2.04 [0.38, 10.89]
2 Acute myocardial infarction	12	10500	Risk Ratio (M‐H, Random, 95% CI)	0.72 [0.60, 0.87]
2.1 Before surgery	6	10002	Risk Ratio (M‐H, Random, 95% CI)	0.73 [0.61, 0.88]
2.2 During surgery	4	272	Risk Ratio (M‐H, Random, 95% CI)	0.14 [0.01, 2.47]
2.3 After surgery	2	226	Risk Ratio (M‐H, Random, 95% CI)	0.39 [0.06, 2.60]
3 Bradycardia	49	12239	Risk Ratio (M‐H, Random, 95% CI)	2.49 [1.74, 3.56]
3.1 Before surgery	13	9528	Risk Ratio (M‐H, Random, 95% CI)	2.89 [1.70, 4.91]
3.2 During surgery	32	2291	Risk Ratio (M‐H, Random, 95% CI)	1.98 [1.17, 3.35]
3.3 After surgery	4	420	Risk Ratio (M‐H, Random, 95% CI)	2.59 [1.54, 4.37]
4 Hypotension	49	12304	Risk Ratio (M‐H, Random, 95% CI)	1.40 [1.29, 1.51]
4.1 Before surgery	11	9354	Risk Ratio (M‐H, Random, 95% CI)	1.37 [1.19, 1.58]
4.2 During surgery	33	2312	Risk Ratio (M‐H, Random, 95% CI)	1.36 [1.12, 1.65]
4.3 After surgery	5	638	Risk Ratio (M‐H, Random, 95% CI)	1.30 [0.65, 2.58]