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Each row is one question a systematic review asked: who, what, compared with what, and which outcome, with the effect it found and how certain that is. Words match anywhere in the field.

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1,558 questions in 115 reviews · Vascular

current versions

No studies 346 · 22.2%Ungraded 90 · 5.8%Very low 281 · 18%Low 477 · 30.6%Moderate 313 · 20.1%High 51 · 3.3%

Ungraded means an effect was reported without a GRADE rating; it is not a gap. No studies means the review found nothing to answer the question. The six categories are a display order, not a score.

Question	Effect	Evidence	Status / GRADE
Anticoagulant vs antiplatelet agent All‐cause mortality · non‐hospitalised people with COVID‐19 Prophylactic anticoagulants for non‐hospitalised people with COVID‐19 (2023) · Cochrane	no estimate extracted	1 study · 279 participants	Moderate
Anticoagulant vs antiplatelet agent Venous thromboembolism · non‐hospitalised people with COVID‐19 Prophylactic anticoagulants for non‐hospitalised people with COVID‐19 (2023) · Cochrane	RR 0.36 [0.01, 8.65]	1 study · 279 participants	Low
Anticoagulant vs antiplatelet agent Major bleeding · non‐hospitalised people with COVID‐19 Prophylactic anticoagulants for non‐hospitalised people with COVID‐19 (2023) · Cochrane	no estimate extracted	1 study · 279 participants	Moderate
Anticoagulant vs antiplatelet agent Deep vein thrombosis · non‐hospitalised people with COVID‐19 Prophylactic anticoagulants for non‐hospitalised people with COVID‐19 (2023) · Cochrane	no estimate extracted	NR	No studies
Anticoagulant vs antiplatelet agent Pulmonary embolism · non‐hospitalised people with COVID‐19 Prophylactic anticoagulants for non‐hospitalised people with COVID‐19 (2023) · Cochrane	no estimate extracted	NR	No studies
Anticoagulant vs placebo or no treatment Venous thromboembolism · non‐hospitalised people with COVID‐19 Prophylactic anticoagulants for non‐hospitalised people with COVID‐19 (2023) · Cochrane	RR 0.36 [0.16, 0.85]	4 studies · 1259 participants	Moderate
Anticoagulant vs antiplatelet agent Need for hospitalisation · non‐hospitalised people with COVID‐19 Prophylactic anticoagulants for non‐hospitalised people with COVID‐19 (2023) · Cochrane	RR 3.2 [0.13, 77.85]	1 study · 279 participants	Low
Anticoagulant vs antiplatelet agent Adverse events (minor bleeding) · non‐hospitalised people with COVID‐19 Prophylactic anticoagulants for non‐hospitalised people with COVID‐19 (2023) · Cochrane	RR 2.13 [0.4, 11.46]	1 study · 279 participants	Low
Anticoagulant vs placebo or no treatment Major bleeding · non‐hospitalised people with COVID‐19 Prophylactic anticoagulants for non‐hospitalised people with COVID‐19 (2023) · Cochrane	RR 0.36 [0.01, 8.78]	5 studies · 1777 participants	Low
Anticoagulant vs placebo or no treatment Deep vein thrombosis · non‐hospitalised people with COVID‐19 Prophylactic anticoagulants for non‐hospitalised people with COVID‐19 (2023) · Cochrane	RR 1.02 [0.3, 3.46]	3 studies · 1009 participants	Moderate
Anticoagulant vs placebo or no treatment Pulmonary embolism · non‐hospitalised people with COVID‐19 Prophylactic anticoagulants for non‐hospitalised people with COVID‐19 (2023) · Cochrane	RR 0.25 [0.08, 0.79]	3 studies · 1009 participants	Moderate
Anticoagulant vs placebo or no treatment Need for hospitalisation · non‐hospitalised people with COVID‐19 Prophylactic anticoagulants for non‐hospitalised people with COVID‐19 (2023) · Cochrane	RR 1.01 [0.59, 1.75]	4 studies · 1459 participants	Moderate
Anticoagulant vs placebo or no treatment Adverse events (minor bleeding) · non‐hospitalised people with COVID‐19 Prophylactic anticoagulants for non‐hospitalised people with COVID‐19 (2023) · Cochrane	RR 2.46 [0.9, 6.72]	5 studies · 1777 participants	Low
Anticoagulant vs different dose of the same anticoagulant All‐cause mortality · non‐hospitalised people with COVID‐19 Prophylactic anticoagulants for non‐hospitalised people with COVID‐19 (2023) · Cochrane	no estimate extracted	1 study · 278 participants	Moderate
Anticoagulant vs different dose of the same anticoagulant Venous thromboembolism · non‐hospitalised people with COVID‐19 Prophylactic anticoagulants for non‐hospitalised people with COVID‐19 (2023) · Cochrane	no estimate extracted	1 study · 278 participants	Moderate
Tourniquet use vs no tourniquet use Intraoperative blood loss (mL) ( · people with PAD undergoing MLLA Tourniquet use for people with peripheral arterial disease undergoing major lower limb amputations (2023) · Cochrane	no estimate extracted	1 study · 54 participants	Low
Tourniquet use vs no tourniquet use Fall in haemoglobin levels(g/L or mmol/L) ( · people with PAD undergoing MLLA Tourniquet use for people with peripheral arterial disease undergoing major lower limb amputations (2023) · Cochrane	no estimate extracted	1 study · 54 participants	Low
Tourniquet use vs no tourniquet use Perioperative blood transfusion requirement ( · people with PAD undergoing MLLA Tourniquet use for people with peripheral arterial disease undergoing major lower limb amputations (2023) · Cochrane	no estimate extracted	1 study · 54 participants	Low
Tourniquet use vs no tourniquet use Primary wound‐healing rates (6 weeks) · people with PAD undergoing MLLA Tourniquet use for people with peripheral arterial disease undergoing major lower limb amputations (2023) · Cochrane	no estimate extracted	1 study · 54 participants	Very low
Tourniquet use vs no tourniquet use Stump revision rates (maximal · people with PAD undergoing MLLA Tourniquet use for people with peripheral arterial disease undergoing major lower limb amputations (2023) · Cochrane	no estimate extracted	1 study · 54 participants	Very low
Tourniquet use vs no tourniquet use Postoperative complications (maximal · people with PAD undergoing MLLA Tourniquet use for people with peripheral arterial disease undergoing major lower limb amputations (2023) · Cochrane	no estimate extracted	1 study · 54 participants	Very low
Tourniquet use vs no tourniquet use Postoperative mortality (6 weeks) · people with PAD undergoing MLLA Tourniquet use for people with peripheral arterial disease undergoing major lower limb amputations (2023) · Cochrane	no estimate extracted	1 study · 54 participants	Very low
IPC plus pharmacological prophylaxis vs IPC alone Incidence of PEa (early postoperative period) · people undergoing surgery or at risk of developing VTE due to surgery, trauma or ICU stay Combined intermittent pneumatic leg compression and pharmacological prophylaxis for prevention of venous… (2022) · Cochrane	OR 0.51 [0.29, 0.91]	19 studies · 5462 participants	Low
IPC plus pharmacological prophylaxis vs IPC alone Incidence of DVTc (early postoperative period) · people undergoing surgery or at risk of developing VTE due to surgery, trauma or ICU stay Combined intermittent pneumatic leg compression and pharmacological prophylaxis for prevention of venous… (2022) · Cochrane	OR 0.51 [0.36, 0.72]	18 studies · 5394 participants	Low
IPC plus pharmacological prophylaxis vs IPC alone Incidence of bleedingd (early postoperative period) · people undergoing surgery or at risk of developing VTE due to surgery, trauma or ICU stay Combined intermittent pneumatic leg compression and pharmacological prophylaxis for prevention of venous… (2022) · Cochrane	OR 6.02 [3.88, 9.35]	13 studies · 4634 participants	Very low
IPC plus pharmacological prophylaxis vs IPC alone Incidence of major bleedingf (early postoperative period) · people undergoing surgery or at risk of developing VTE due to surgery, trauma or ICU stay Combined intermittent pneumatic leg compression and pharmacological prophylaxis for prevention of venous… (2022) · Cochrane	OR 5.77 [2.81, 11.83]	12 studies · 4133 participants	Very low
IPC plus pharmacological prophylaxis vs pharmacological prophylaxis alone Incidence of PEa (early postoperative period) · people undergoing surgery or at risk of developing VTE because of surgery, trauma or ICU stay Combined intermittent pneumatic leg compression and pharmacological prophylaxis for prevention of venous… (2022) · Cochrane	OR 0.46 [0.3, 0.71]	15 studies · 6737 participants	Low
IPC plus pharmacological prophylaxis vs pharmacological prophylaxis alone Incidence of DVTc (early postoperative period) · people undergoing surgery or at risk of developing VTE because of surgery, trauma or ICU stay Combined intermittent pneumatic leg compression and pharmacological prophylaxis for prevention of venous… (2022) · Cochrane	OR 0.38 [0.21, 0.7]	17 studies · 6151 participants	High
IPC plus pharmacological prophylaxis vs pharmacological prophylaxis alone Incidence of bleedinge (early postoperative period) · people undergoing surgery or at risk of developing VTE because of surgery, trauma or ICU stay Combined intermittent pneumatic leg compression and pharmacological prophylaxis for prevention of venous… (2022) · Cochrane	OR 0.87	6 studies · 1314 participants	Very low
IPC plus pharmacological prophylaxis vs pharmacological prophylaxis alone Incidence of major bleedingg (early postoperative period) · people undergoing surgery or at risk of developing VTE because of surgery, trauma or ICU stay Combined intermittent pneumatic leg compression and pharmacological prophylaxis for prevention of venous… (2022) · Cochrane	OR 1.21 [0.35, 4.18]	5 studies · 908 participants	Very low
Low‐molecular‐weight heparin vs no prophylaxis PE: assessed by CT arteriography ( · adults undergoing KA Interventions for preventing venous thromboembolism in adults undergoing knee arthroscopy (2022) · Cochrane	RR 1.81 [0.49, 6.65]	3 studies · 1820 participants	Moderate
Low‐molecular‐weight heparin vs no prophylaxis Symptomatic DVT: assessed by presence of symptoms and confirmed by a positive compression ultrasound ( · adults undergoing KA Interventions for preventing venous thromboembolism in adults undergoing knee arthroscopy (2022) · Cochrane	RR 0.61 [0.18, 2.03]	4 studies · 1848 participants	Low
Low‐molecular‐weight heparin vs no prophylaxis Asymptomatic DVT: · adults undergoing KA Interventions for preventing venous thromboembolism in adults undergoing knee arthroscopy (2022) · Cochrane	RR 0.14 [0.03, 0.61]	2 studies · 369 participants	Very low
Low‐molecular‐weight heparin vs no prophylaxis All‐cause mortality ( · adults undergoing KA Interventions for preventing venous thromboembolism in adults undergoing knee arthroscopy (2022) · Cochrane	no estimate extracted	5 studies · 1978 participants	Ungraded
Low‐molecular‐weight heparin vs no prophylaxis All adverse effects, including allergies at injection site, minor and major bleeding, others ( · adults undergoing KA Interventions for preventing venous thromboembolism in adults undergoing knee arthroscopy (2022) · Cochrane	RR 1.85 [0.95, 3.59]	5 studies · 1978 participants	Moderate
Low‐molecular‐weight heparin vs no prophylaxis Major bleeding ( · adults undergoing KA Interventions for preventing venous thromboembolism in adults undergoing knee arthroscopy (2022) · Cochrane	RR 0.98 [0.06, 15.72]	1 study · 1451 participants	Moderate
Low‐molecular‐weight heparin vs no prophylaxis Minor bleeding ( · adults undergoing KA Interventions for preventing venous thromboembolism in adults undergoing knee arthroscopy (2022) · Cochrane	RR 1.79 [0.84, 3.84]	5 studies · 1978 participants	Moderate
Intramuscular injection of bone marrow mononuclear cells (BMMNC) vs control All‐cause mortality ( · people with CLI who were not suitable for revascularisation and showed no improvement in response to the best standard… Local intramuscular transplantation of autologous bone marrow mononuclear cells for critical lower limb… (2022) · Cochrane	RR 1 [0.15, 6.63]	3 studies · 123 participants	Very low
Intramuscular injection of bone marrow mononuclear cells (BMMNC) vs control Reduction in pain Various scales including VAS, PISQ; scales ranged from 0 to 4/10/100, where 0 = no pain ( · people with CLI who were not suitable for revascularisation and showed no improvement in response to the best standard… Local intramuscular transplantation of autologous bone marrow mononuclear cells for critical lower limb… (2022) · Cochrane	no estimate extracted	4 studies · 176 participants	Very low
Intramuscular injection of bone marrow mononuclear cells (BMMNC) vs control Incidence of amputation ( · people with CLI who were not suitable for revascularisation and showed no improvement in response to the best standard… Local intramuscular transplantation of autologous bone marrow mononuclear cells for critical lower limb… (2022) · Cochrane	RR 0.52 [0.27, 0.99]	4 studies · 176 participants	Very low
Intramuscular injection of bone marrow mononuclear cells (BMMNC) vs control Angiographic analysis · people with CLI who were not suitable for revascularisation and showed no improvement in response to the best standard… Local intramuscular transplantation of autologous bone marrow mononuclear cells for critical lower limb… (2022) · Cochrane	no estimate extracted	NR	No studies
Intramuscular injection of bone marrow mononuclear cells (BMMNC) vs control Increase in ABI An ABI ratio of 0.9 or less indicates PAD. Values between 0.9 and 1.0 are borderline, and above 1.0 is considered normal ( · people with CLI who were not suitable for revascularisation and showed no improvement in response to the best standard… Local intramuscular transplantation of autologous bone marrow mononuclear cells for critical lower limb… (2022) · Cochrane	no estimate extracted	4 studies · 176 participants	Very low
Intramuscular injection of bone marrow mononuclear cells (BMMNC) vs control Increase in PFWD (m) ( · people with CLI who were not suitable for revascularisation and showed no improvement in response to the best standard… Local intramuscular transplantation of autologous bone marrow mononuclear cells for critical lower limb… (2022) · Cochrane	no estimate extracted	1 study · 53 participants	Low
Intramuscular injection of bone marrow mononuclear cells (BMMNC) vs control Side effects and complications ( · people with CLI who were not suitable for revascularisation and showed no improvement in response to the best standard… Local intramuscular transplantation of autologous bone marrow mononuclear cells for critical lower limb… (2022) · Cochrane	RR 2.13 [0.5, 8.97]	4 studies · 176 participants	Very low
Heparin vs normal saline solution locking Occlusion of CVC (combining participant, and catheter as unit of analysis) Blood withdrawing · adults with CVCs Heparin versus 0.9% sodium chloride locking for prevention of occlusion in central venous catheters in adults (2022) · Cochrane	RR 0.7 [0.51, 0.95]	10 studies · 1672 participants	Low
Heparin vs normal saline solution locking Duration of catheter patency (days; combining participant and catheter as unit of analysis) Blood withdrawing · adults with CVCs Heparin versus 0.9% sodium chloride locking for prevention of occlusion in central venous catheters in adults (2022) · Cochrane	no estimate extracted	6 studies · 1788 participants	Low
Heparin vs normal saline solution locking CVC‐related bloodstream infections (positive microbiological culture, participant as unit of analysis) · adults with CVCs Heparin versus 0.9% sodium chloride locking for prevention of occlusion in central venous catheters in adults (2022) · Cochrane	RR 0.66 [0.08, 5.8]	3 studies · 1127 participants	Very low
Heparin vs normal saline solution locking Mortality · adults with CVCs Heparin versus 0.9% sodium chloride locking for prevention of occlusion in central venous catheters in adults (2022) · Cochrane	RR 0.76 [0.44, 1.31]	3 studies · 1100 participants	Very low
Heparin vs normal saline solution locking Haemorrhage from any site · adults with CVCs Heparin versus 0.9% sodium chloride locking for prevention of occlusion in central venous catheters in adults (2022) · Cochrane	RR 1.54	3 studies · 1197 participants	Very low
Heparin vs normal saline solution locking Heparin‐induced thrombocytopaenia · adults with CVCs Heparin versus 0.9% sodium chloride locking for prevention of occlusion in central venous catheters in adults (2022) · Cochrane	RR 0.21 [0.01, 4.27]	3 studies · 443 participants	Very low