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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.

Population

Intervention or exposure

Comparison

Outcome

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Field or topic

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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
Low‐molecular‐weight heparin vs active control (3) Clinically relevant bleeding · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	no estimate extracted	NR	No studies
Ultra‐low‐molecular‐weight heparin vs placebo Symptomatic VTE · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 0.36 [0.22, 0.6]	1 study · 3212 participants	High
Ultra‐low‐molecular‐weight heparin vs placebo Major bleeding · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 1.05 [0.55, 2]	1 study · 3172 participants	Moderate
Ultra‐low‐molecular‐weight heparin vs placebo Symptomatic PE · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 0.48 [0.22, 1.01]	1 study · 3212 participants	Moderate
Ultra‐low‐molecular‐weight heparin vs placebo Symptomatic DVT · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 0.32 [0.16, 0.63]	1 study · 3212 participants	High
DOAC vs placebo Symptomatic DVT · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 0.51 [0.21, 1.22]	3 studies · 1526 participants	Low
Ultra‐low‐molecular‐weight heparin vs placebo Any VTE · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 0.36 [0.22, 0.6]	1 study · 3212 participants	High
Ultra‐low‐molecular‐weight heparin vs placebo 1‐year overall mortality · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 1.02 [0.96, 1.08]	1 study · 3212 participants	Moderate
Ultra‐low‐molecular‐weight heparin vs placebo Clinically relevant bleeding · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 1.4 [0.9, 2.19]	1 study · 3172 participants	Moderate
Unfractionated heparin vs no thromboprophylaxis Symptomatic VTE · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	no estimate extracted	NR	No studies
Unfractionated heparin vs no thromboprophylaxis Major bleeding · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	no estimate extracted	NR	No studies
Unfractionated heparin vs no thromboprophylaxis Symptomatic PE · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	no estimate extracted	NR	No studies
Unfractionated heparin vs no thromboprophylaxis Symptomatic DVT · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	no estimate extracted	NR	No studies
Unfractionated heparin vs no thromboprophylaxis Any VTE · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	no estimate extracted	NR	No studies
Unfractionated heparin vs no thromboprophylaxis 1‐year overall mortality · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 0.86 [0.72, 1.03]	1 study · 277 participants	Moderate
Unfractionated heparin vs no thromboprophylaxis Clinically relevant bleeding · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 2.01 [0.18, 21.96]	1 study · 277 participants	Low
DOAC vs placebo Any VTE · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 0.55 [0.34, 0.9]	2 studies · 1404 participants	Moderate
Vitamin K antagonists vs placebo or no thromboprophylaxis Symptomatic VTE · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 0.15 [0.02, 1.2]	1 study · 311 participants	Low
Vitamin K antagonists vs placebo or no thromboprophylaxis Major bleeding · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 3.82 [0.97, 15.04]	4 studies · 994 participants	Low
Vitamin K antagonists vs placebo or no thromboprophylaxis Symptomatic PE · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 1.05 [0.07, 16.58]	1 study · 311 participants	Very low
Vitamin K antagonists vs placebo or no thromboprophylaxis Symptomatic DVT · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 0.08 [0, 1.42]	1 study · 311 participants	Low
Vitamin K antagonists vs placebo or no thromboprophylaxis Any VTE · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	no estimate extracted	NR	No studies
Vitamin K antagonists vs placebo or no thromboprophylaxis 1‐year overall mortality · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	no estimate extracted	NR	No studies
Vitamin K antagonists vs placebo or no thromboprophylaxis Clinically relevant bleeding · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	no estimate extracted	NR	No studies
Vitamin K antagonists vs active control Symptomatic VTE · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 1.5 [0.74, 3.04]	1 study · 440 participants	Moderate
Vitamin K antagonists vs active control Major bleeding · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 0.14 [0.01, 2.75]	1 study · 440 participants	Low
Vitamin K antagonists vs active control Symptomatic PE · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 1 [0.25, 3.95]	1 study · 440 participants	Moderate
DOAC vs placebo 1‐year overall mortality · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	no estimate extracted	0 studies · 0 participants	Ungraded
Vitamin K antagonists vs active control Symptomatic DVT · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 1.75 [0.75, 4.09]	1 study · 440 participants	Moderate
Vitamin K antagonists vs active control Any VTE · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	no estimate extracted	NR	No studies
Vitamin K antagonists vs active control 1‐year overall mortality · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	no estimate extracted	NR	No studies
Vitamin K antagonists vs active control Clinically relevant bleeding · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	no estimate extracted	NR	No studies
Antithrombin vs no thromboprophylaxis Symptomatic VTE · ambulatory paediatric cancer patients newly diagnosed with acute lymphoblastic leukaemia who received chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	no estimate extracted	NR	No studies
Antithrombin vs no thromboprophylaxis Major bleeding · ambulatory paediatric cancer patients newly diagnosed with acute lymphoblastic leukaemia who received chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 0.78 [0.03, 18.57]	1 study · 85 participants	Very low
Antithrombin vs no thromboprophylaxis Symptomatic PE · ambulatory paediatric cancer patients newly diagnosed with acute lymphoblastic leukaemia who received chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	no estimate extracted	NR	No studies
Antithrombin vs no thromboprophylaxis Symptomatic DVT · ambulatory paediatric cancer patients newly diagnosed with acute lymphoblastic leukaemia who received chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	no estimate extracted	NR	No studies
Antithrombin vs no thromboprophylaxis Any VTE · ambulatory paediatric cancer patients newly diagnosed with acute lymphoblastic leukaemia who received chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 0.84 [0.41, 1.73]	1 study · 85 participants	Very low
Antithrombin vs no thromboprophylaxis 1‐year overall mortality · ambulatory paediatric cancer patients newly diagnosed with acute lymphoblastic leukaemia who received chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	no estimate extracted	NR	No studies
DOAC vs placebo Clinically relevant bleeding · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 1.61 [0.82, 3.15]	2 studies · 931 participants	Moderate
Antithrombin vs no thromboprophylaxis Clinically relevant bleeding · ambulatory paediatric cancer patients newly diagnosed with acute lymphoblastic leukaemia who received chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	no estimate extracted	NR	No studies
Low‐molecular‐weight heparin vs no thromboprophylaxis Symptomatic VTE · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 0.62 [0.46, 0.83]	11 studies · 3931 participants	High
Low‐molecular‐weight heparin vs no thromboprophylaxis Major bleeding · ambulatory cancer patients receiving chemotherapy Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (2020) · Cochrane	RR 1.63 [1.12, 2.35]	15 studies · 7282 participants	Moderate
Alternative modes of exercise vs walking exercise Maximum walking distance (12 weeks) · patients with IC Modes of exercise training for intermittent claudication (2020) · Cochrane	no estimate extracted	6 studies · 274 participants	Low
Alternative modes of exercise vs walking exercise Maximum walking distance (at end of training, ranging from 6 to 24 weeks) · patients with IC Modes of exercise training for intermittent claudication (2020) · Cochrane	no estimate extracted	9 studies · 412 participants	Low
Alternative modes of exercise vs walking exercise Pain‐free walking distance (12 weeks) · patients with IC Modes of exercise training for intermittent claudication (2020) · Cochrane	no estimate extracted	5 studies · 249 participants	Low
Alternative modes of exercise vs walking exercise Pain‐free walking distance (at end of training, ranging from 6 to 24 weeks) · patients with IC Modes of exercise training for intermittent claudication (2020) · Cochrane	no estimate extracted	8 studies · 382 participants	Low
Alternative modes of exercise vs walking exercise Health‐related QoL (at end of training, ranging from 12 to 24 weeks) · patients with IC Modes of exercise training for intermittent claudication (2020) · Cochrane	no estimate extracted	NR	No studies
Alternative modes of exercise vs walking exercise Self‐reported functional impairment (WIQ) (at end of training, ranging from 12 to 24 weeks) · patients with IC Modes of exercise training for intermittent claudication (2020) · Cochrane	no estimate extracted	2 studies · 96 participants	Low
Low molecular weight heparin vs unfractionated heparin Success rate of replantation1 (analysed by participant, · patients undergoing digital replantation after traumatic amputation Low molecular weight heparin for prevention of microvascular occlusion in digital replantation (2020) · Cochrane	RR 0.98 [0.87, 1.1]	2 studies · 130 participants	Very low
Low molecular weight heparin (LMWH) vs no LMWH Incidence of compromised microcirculation requiring invasive intervention (re‐exploration) (analysed by digit, · patients undergoing digital replantation after traumatic amputation Low molecular weight heparin for prevention of microvascular occlusion in digital replantation (2020) · Cochrane	RR 0.86 [0.21, 3.58]	1 study · 73 participants	Very low