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Search review questions

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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Intervention or exposure

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Review versions

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
Exercise vs no exercise Perioperative and postoperative: need for re‐intervention · adults with clinically diagnosed AAA deemed suitable for elective repair Prehabilitation exercise therapy before elective abdominal aortic aneurysm repair (2021) · Cochrane	RR 1.29 [0.33, 4.96]	2 studies · 144 participants	Very low
Exercise vs no exercise Perioperative and postoperative complications: postoperative bleeding · adults with clinically diagnosed AAA deemed suitable for elective repair Prehabilitation exercise therapy before elective abdominal aortic aneurysm repair (2021) · Cochrane	RR 0.57 [0.18, 1.8]	1 study · 124 participants	Very low
Exercise vs no exercise Length of ICU stay (days) · adults with clinically diagnosed AAA deemed suitable for elective repair Prehabilitation exercise therapy before elective abdominal aortic aneurysm repair (2021) · Cochrane	no estimate extracted	2 studies · 147 participants	Very low
Exercise vs no exercise Length of hospital stay (days) · adults with clinically diagnosed AAA deemed suitable for elective repair Prehabilitation exercise therapy before elective abdominal aortic aneurysm repair (2021) · Cochrane	no estimate extracted	3 studies · 212 participants	Very low
Exercise vs no exercise Number of days on a ventilator · adults with clinically diagnosed AAA deemed suitable for elective repair Prehabilitation exercise therapy before elective abdominal aortic aneurysm repair (2021) · Cochrane	no estimate extracted	NR	No studies
Early open repair vs ultrasound surveillance Mortality ( · small asymptomatic AAA Surgery for small asymptomatic abdominal aortic aneurysms (2020) · Cochrane	HR 0.99	2 studies · 2226 participants	High
Early open repair vs ultrasound surveillance Costs (per participant) ( · small asymptomatic AAA Surgery for small asymptomatic abdominal aortic aneurysms (2020) · Cochrane	no estimate extracted	1 study · 1090 participants	Moderate
Early open repair vs ultrasound surveillance QoLc ( · small asymptomatic AAA Surgery for small asymptomatic abdominal aortic aneurysms (2020) · Cochrane	no estimate extracted	2 studies · 2226 participants	Ungraded
Early open repair vs ultrasound surveillance Aneurysm rupture ( · small asymptomatic AAA Surgery for small asymptomatic abdominal aortic aneurysms (2020) · Cochrane	no estimate extracted	2 studies · 2226 participants	Ungraded
Early endovascular repair vs ultrasound surveillance Mortality ( · small asymptomatic AAA Surgery for small asymptomatic abdominal aortic aneurysms (2020) · Cochrane	RR 1.92 [0.73, 5.06]	2 studies · 846 participants	Low
Early endovascular repair vs ultrasound surveillance Costs ( · small asymptomatic AAA Surgery for small asymptomatic abdominal aortic aneurysms (2020) · Cochrane	MD 27	1 study · 614 participants	Low
Early endovascular repair vs ultrasound surveillance Costs ( · small asymptomatic AAA Surgery for small asymptomatic abdominal aortic aneurysms (2020) · Cochrane	MD 2557	1 study · 614 participants	Low
Early endovascular repair vs ultrasound surveillance QoL ( · small asymptomatic AAA Surgery for small asymptomatic abdominal aortic aneurysms (2020) · Cochrane	no estimate extracted	2 studies · 605 participants	Ungraded
Early endovascular repair vs ultrasound surveillance Aneurysm rupture (overall · small asymptomatic AAA Surgery for small asymptomatic abdominal aortic aneurysms (2020) · Cochrane	no estimate extracted	2 studies · 1088 participants	Ungraded
Intervention NR Time to ulcer healing · participants with arterial ulcersa Dressings and topical agents for arterial leg ulcers (2020) · Cochrane	no estimate extracted	NR	No studies
Intervention NR Change in ulcer area over time (6 ‐ 8 weeks) · participants with arterial ulcersa Dressings and topical agents for arterial leg ulcers (2020) · Cochrane	no estimate extracted	2 studies · 49 participants	Very low
Intervention NR Complications and morbidity (6 ‐ 8 weeks) · participants with arterial ulcersa Dressings and topical agents for arterial leg ulcers (2020) · Cochrane	no estimate extracted	2 studies · 49 participants	Low
Intervention NR Patient satisfaction and quality of life data · participants with arterial ulcersa Dressings and topical agents for arterial leg ulcers (2020) · Cochrane	no estimate extracted	NR	No studies
EDTA vs placebo All‐cause mortality · atherosclerotic cardiovascular disease Chelation therapy for atherosclerotic cardiovascular disease (2020) · Cochrane	RR 0.97 [0.73, 1.28]	2 studies · 1792 participants	Low
EDTA vs placebo Coronary heart disease death · atherosclerotic cardiovascular disease Chelation therapy for atherosclerotic cardiovascular disease (2020) · Cochrane	RR 1.02 [0.7, 1.48]	1 study · 1708 participants	Very low
EDTA vs placebo Myocardial infarction · atherosclerotic cardiovascular disease Chelation therapy for atherosclerotic cardiovascular disease (2020) · Cochrane	RR 0.81 [0.57, 1.14]	2 studies · 1792 participants	Moderate
EDTA vs placebo Angina · atherosclerotic cardiovascular disease Chelation therapy for atherosclerotic cardiovascular disease (2020) · Cochrane	RR 0.95 [0.55, 1.67]	2 studies · 1792 participants	Very low
EDTA vs placebo Stroke · atherosclerotic cardiovascular disease Chelation therapy for atherosclerotic cardiovascular disease (2020) · Cochrane	RR 0.88 [0.4, 1.92]	2 studies · 1867 participants	Low
EDTA vs placebo Ankle‐brachial pressure index at 3 months post‐treatment · atherosclerotic cardiovascular disease Chelation therapy for atherosclerotic cardiovascular disease (2020) · Cochrane	no estimate extracted	2 studies · 181 participants	Low
EDTA vs placebo Maximum walking distance (m) at 3 months post‐treatment · atherosclerotic cardiovascular disease Chelation therapy for atherosclerotic cardiovascular disease (2020) · Cochrane	no estimate extracted	2 studies · 165 participants	Low
Do phlebotonics improve signs and symptoms of venous insufficiency when vs placebo? Oedema in the lower legs (dichotomous variable) · patients with venous insufficiency Phlebotonics for venous insufficiency (2020) · Cochrane	RR 0.7 [0.63, 0.78]	13 studies · 1245 participants	Moderate
Do phlebotonics improve signs and symptoms of venous insufficiency when vs placebo? Oedema in the lower legs (ankle circumference, mm) · patients with venous insufficiency Phlebotonics for venous insufficiency (2020) · Cochrane	no estimate extracted	15 studies · 2010 participants	Moderate
Do phlebotonics improve signs and symptoms of venous insufficiency when vs placebo? Quality of life (CIVIQ and other questionnaires) · patients with venous insufficiency Phlebotonics for venous insufficiency (2020) · Cochrane	no estimate extracted	5 studies · 1639 participants	Moderate
Do phlebotonics improve signs and symptoms of venous insufficiency when vs placebo? Ulcer healing (dichotomous variable) · patients with venous insufficiency Phlebotonics for venous insufficiency (2020) · Cochrane	RR 0.94 [0.79, 1.13]	6 studies · 461 participants	Low
Do phlebotonics improve signs and symptoms of venous insufficiency when vs placebo? Adverse events · patients with venous insufficiency Phlebotonics for venous insufficiency (2020) · Cochrane	RR 1.14 [1.02, 1.27]	37 studies · 5789 participants	Moderate
Pentoxifylline vs placebo PFWD (change in metres) (4–40 weeks' · people with intermittent claudication Pentoxifylline for intermittent claudication (2020) · Cochrane	no estimate extracted	11 studies · 1890 participants	Low
Pentoxifylline vs placebo TWD (change in metres) (8–52 weeks' · people with intermittent claudication Pentoxifylline for intermittent claudication (2020) · Cochrane	no estimate extracted	14 studies · 2110 participants	Low
Pentoxifylline vs placebo ABI (pre‐exercise/baseline ABI compared with · people with intermittent claudication Pentoxifylline for intermittent claudication (2020) · Cochrane	no estimate extracted	5 studies · 902 participants	Moderate
Pentoxifylline vs placebo QoL (SF‐36, WIQ and unspecified) (1 study with 4 weeks' · people with intermittent claudication Pentoxifylline for intermittent claudication (2020) · Cochrane	no estimate extracted	3 studies · 1179 participants	Moderate
Pentoxifylline vs placebo Side effects (number of cases or proportion) (4–52 weeks' · people with intermittent claudication Pentoxifylline for intermittent claudication (2020) · Cochrane	no estimate extracted	9 studies · 1837 participants	Low
Does low molecular weight heparin prevent central venous catheter‐related thrombosis vs control CVC‐related thrombosis ( · children with a CVC Low molecular weight heparin for prevention of central venous catheter‐related thrombosis in children (2020) · Cochrane	RR 0.68 [0.27, 1.75]	2 studies · 787 participants	Low
Does low molecular weight heparin prevent central venous catheter‐related thrombosis vs control Symptomatic CVC‐related thrombosis ( · children with a CVC Low molecular weight heparin for prevention of central venous catheter‐related thrombosis in children (2020) · Cochrane	RR 1.03 [0.21, 4.93]	1 study · 158 participants	Low
Does low molecular weight heparin prevent central venous catheter‐related thrombosis vs control Asymptomatic CVC‐related thrombosis ( · children with a CVC Low molecular weight heparin for prevention of central venous catheter‐related thrombosis in children (2020) · Cochrane	RR 1.17 [0.45, 3.08]	1 study · 158 participants	Low
Does low molecular weight heparin prevent central venous catheter‐related thrombosis vs control Major bleeding ( · children with a CVC Low molecular weight heparin for prevention of central venous catheter‐related thrombosis in children (2020) · Cochrane	RR 0.27 [0.05, 1.67]	2 studies · 813 participants	Low
Does low molecular weight heparin prevent central venous catheter‐related thrombosis vs control Minor bleeding ( · children with a CVC Low molecular weight heparin for prevention of central venous catheter‐related thrombosis in children (2020) · Cochrane	no estimate extracted	2 studies · 813 participants	Very low
Does low molecular weight heparin prevent central venous catheter‐related thrombosis vs control Mortality during study period ( · children with a CVC Low molecular weight heparin for prevention of central venous catheter‐related thrombosis in children (2020) · Cochrane	no estimate extracted	2 studies · 813 participants	Low
Retrievable vena caval filters with anticoagulation vs anticoagulation PE: recurrent fatal and non‐fatal PE, demonstrated by CT, pulmonary angiography or ventilation‐perfusion lung scan (up to 6 months) · participants with unprovoked acute symptomatic PE and at high risk for recurrent PEa Vena caval filters for the prevention of pulmonary embolism (2020) · Cochrane	RR 1.74 [0.52, 5.86]	1 study · 399 participants	Moderate
Retrievable vena caval filters with anticoagulation vs anticoagulation Major bleedingd (at 90 days) · participants who sustained multiple traumatic injuriesa Vena caval filters for the prevention of pulmonary embolism (2020) · Cochrane	no estimate extracted	1 study · 240 participants	Moderate
Retrievable vena caval filters with anticoagulation vs anticoagulation Mortality (up to 6 months) · participants with unprovoked acute symptomatic PE and at high risk for recurrent PEa Vena caval filters for the prevention of pulmonary embolism (2020) · Cochrane	RR 1.39 [0.74, 2.62]	1 study · 399 participants	Moderate
Retrievable vena caval filters with anticoagulation vs anticoagulation Symtomatic lower extremity venous thrombosis confirmed by Doppler ultrasound or venography (up to 6 months) · participants with unprovoked acute symptomatic PE and at high risk for recurrent PEa Vena caval filters for the prevention of pulmonary embolism (2020) · Cochrane	RR 0.5 [0.05, 5.44]	1 study · 399 participants	Moderate
Retrievable vena caval filters with anticoagulation vs anticoagulation Filter‐related complications (up to 6 months) · participants with unprovoked acute symptomatic PE and at high risk for recurrent PEa Vena caval filters for the prevention of pulmonary embolism (2020) · Cochrane	no estimate extracted	1 study · 399 participants	Ungraded
Retrievable vena caval filters with anticoagulation vs anticoagulation Major bleedingc (up to 6 months) · participants with unprovoked acute symptomatic PE and at high risk for recurrent PEa Vena caval filters for the prevention of pulmonary embolism (2020) · Cochrane	RR 0.86 [0.42, 1.77]	1 study · 399 participants	Moderate
Retrievable vena caval filters with anticoagulation vs anticoagulation Symptomatic PE recurrent; as demonstrated by CT, pulmonary angiography, or post‐mortem, at 90 days · participants who sustained multiple traumatic injuriesa Vena caval filters for the prevention of pulmonary embolism (2020) · Cochrane	no estimate extracted	1 study · 80 participants	Moderate
Retrievable vena caval filters with anticoagulation vs anticoagulation Mortality from any cause (up to 90 days) · participants who sustained multiple traumatic injuriesa Vena caval filters for the prevention of pulmonary embolism (2020) · Cochrane	no estimate extracted	1 study · 240 participants	Moderate
Retrievable vena caval filters with anticoagulation vs anticoagulation Lower extremity venous thrombosis confirmed by Doppler ultrasound or venography (at 14 days) · participants who sustained multiple traumatic injuriesa Vena caval filters for the prevention of pulmonary embolism (2020) · Cochrane	no estimate extracted	1 study · 240 participants	Moderate