Comparison 9. Anticoagulants versus control: incidental venous thromboembolism.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
9.1 Incidental VTE: DOAC vs placebo	2	1404	Risk Ratio (IV, Random, 95% CI)	0.50 [0.25, 0.98]
9.1.1 Apixaban	1	563	Risk Ratio (IV, Random, 95% CI)	0.48 [0.12, 1.89]
9.1.2 Rivaroxaban	1	841	Risk Ratio (IV, Random, 95% CI)	0.50 [0.23, 1.10]
9.2 Incidental VTE: LMWH vs no thromboprophylaxis	5	4452	Risk Ratio (IV, Random, 95% CI)	0.63 [0.40, 0.99]
9.2.1 Dalteparin	3	2419	Risk Ratio (IV, Random, 95% CI)	0.58 [0.34, 1.00]
9.2.2 Nadroparin	1	1150	Risk Ratio (IV, Random, 95% CI)	0.74 [0.21, 2.62]
9.2.3 Certoparin	1	883	Risk Ratio (IV, Random, 95% CI)	0.75 [0.26, 2.14]
9.3 Incidental VTE: prophylactic vs intermediate or therapeutic LMWH	1		Risk Ratio (IV, Fixed, 95% CI)	Subtotals only
9.3.1 Prophylactic vs intermediate	1	51	Risk Ratio (IV, Fixed, 95% CI)	2.89 [0.12, 67.75]
9.3.2 Prophylactic vs therapeutic	1	52	Risk Ratio (IV, Fixed, 95% CI)	3.00 [0.13, 70.42]
9.4 Incidental VTE: semuloparin vs placebo	1	3212	Risk Ratio (IV, Fixed, 95% CI)	0.14 [0.01, 2.76]