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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.
1,590 questions in 129 reviews · Gynaecological, Neuro-oncology and Orphan Cancer
current versionsNo studies 281 · 17.7%Ungraded 74 · 4.7%Very low 410 · 25.8%Low 420 · 26.4%Moderate 280 · 17.6%High 125 · 7.9%
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 |
|---|---|---|---|
Hyperbaric oxygen vs air breathing Quality of life ‐ not reported · People with any one of a mixed group of cancers Hyperbaric oxygenation for tumour sensitisation to radiotherapy (2018) · Cochrane | no estimate extracted | NR | No studies |
Hyperbaric oxygen vs air breathing Adverse effects · People with any one of a mixed group of cancers Hyperbaric oxygenation for tumour sensitisation to radiotherapy (2018) · Cochrane | RR 2.35 [1.66, 3.33] | 7 studies · 779 participants | High |
Hyperbaric oxygen vs air breathing to enhance the effectiveness of radiotherapy Failure of local tumour control (local control) · People undergoing radiation therapy for head and neck cancer Hyperbaric oxygenation for tumour sensitisation to radiotherapy (2018) · Cochrane | RR 0.58 [0.39, 0.85] | 4 studies · 446 participants | Moderate |
Hyperbaric oxygen vs air breathing to enhance the effectiveness of radiotherapy Local recurrence (recurrence ) · People undergoing radiation therapy for head and neck cancer Hyperbaric oxygenation for tumour sensitisation to radiotherapy (2018) · Cochrane | RR 0.66 [0.56, 0.78] | 5 studies · 582 participants | High |
Hyperbaric oxygen vs air breathing to enhance the effectiveness of radiotherapy Metastasis · People undergoing radiation therapy for head and neck cancer Hyperbaric oxygenation for tumour sensitisation to radiotherapy (2018) · Cochrane | RR 0.45 [0.09, 2.3] | 1 study · 50 participants | Moderate |
Hyperbaric oxygen vs air breathing to enhance the effectiveness of radiotherapy Quality of life ‐ not reported · People undergoing radiation therapy for head and neck cancer Hyperbaric oxygenation for tumour sensitisation to radiotherapy (2018) · Cochrane | no estimate extracted | NR | No studies |
Hyperbaric oxygen vs air breathing to enhance the effectiveness of radiotherapy Adverse effects · People undergoing radiation therapy for head and neck cancer Hyperbaric oxygenation for tumour sensitisation to radiotherapy (2018) · Cochrane | RR 2.64 [1.65, 4.23] | 4 studies · 323 participants | Moderate |
Hyperbaric oxygen vs air breathing Mortality · People undergoing radiotherapy for uterine cervical cancer Hyperbaric oxygenation for tumour sensitisation to radiotherapy (2018) · Cochrane | RR 0.88 [0.69, 1.11] | 4 studies · 728 participants | High |
Hyperbaric oxygen vs air breathing Failure of local tumour control ‐ not reported · People undergoing radiotherapy for uterine cervical cancer Hyperbaric oxygenation for tumour sensitisation to radiotherapy (2018) · Cochrane | no estimate extracted | NR | No studies |
Hyperbaric oxygen vs air breathing Local recurrence (recurrence) · People undergoing radiotherapy for uterine cervical cancer Hyperbaric oxygenation for tumour sensitisation to radiotherapy (2018) · Cochrane | RR 0.82 [0.63, 1.06] | 3 studies · 714 participants | High |
Highest vs lowest selenium exposure Any cancer risk No. of participants: 19,475 (3 RCTs) · Participants in trials with low risk of bias Selenium for preventing cancer (2018) · Cochrane | RR 1.01 [0.93, 1.1] | NR | High |
Highest vs lowest selenium exposure Cancer mortality risk No. of participants: 183,863 (7 observational studies) · Participants in non experimental cohort studies on selenium and cancer Selenium for preventing cancer (2018) · Cochrane | OR 0.76 [0.59, 0.97] | NR | Very low |
Highest vs lowest selenium exposure Colorectal cancer risk No. of participants: 712,746 (6 observational studies) · Participants in non experimental cohort studies on selenium and cancer Selenium for preventing cancer (2018) · Cochrane | OR 0.82 [0.72, 0.94] | NR | Very low |
Highest vs lowest selenium exposure Lung cancer risk No. of participants: 371,067 (11 observational studies) · Participants in non experimental cohort studies on selenium and cancer Selenium for preventing cancer (2018) · Cochrane | OR 0.82 [0.59, 1.14] | NR | Very low |
Highest vs lowest selenium exposure Breast cancer risk (women) No. of participants: 169,028 (8 observational studies) · Participants in non experimental cohort studies on selenium and cancer Selenium for preventing cancer (2018) · Cochrane | OR 1.09 [0.87, 1.37] | NR | Very low |
Highest vs lowest selenium exposure Bladder cancer risk No. of participants: 279,100 (5 observational studies) · Participants in non experimental cohort studies on selenium and cancer Selenium for preventing cancer (2018) · Cochrane | OR 0.67 [0.46, 0.97] | NR | Very low |
Highest vs lowest selenium exposure Prostate cancer risk No. of participants: 576,667 (21 observational studies) · Participants in non experimental cohort studies on selenium and cancer Selenium for preventing cancer (2018) · Cochrane | OR 0.84 [0.75, 0.95] | NR | Very low |
Highest vs lowest selenium exposure Cancer mortality risk No. of participants: 17,448 (1 RCT) · Participants in trials with low risk of bias Selenium for preventing cancer (2018) · Cochrane | RR 1.02 [0.8, 1.3] | NR | High |
Highest vs lowest selenium exposure Colorectal cancer risk No. of participants: 19,009 (2 RCTs) · Participants in trials with low risk of bias Selenium for preventing cancer (2018) · Cochrane | RR 0.99 [0.69, 1.43] | NR | High |
Highest vs lowest selenium exposure Non‐melanoma skin cancer risk No. of participants: 2027 (2 RCTs) · Participants in trials with low risk of bias Selenium for preventing cancer (2018) · Cochrane | RR 1.16 [0.3, 4.42] | NR | Moderate |
Highest vs lowest selenium exposure Lung cancer risk No. of participants: 19,009 (2 RCTs) · Participants in trials with low risk of bias Selenium for preventing cancer (2018) · Cochrane | RR 1.16 [0.89, 1.5] | NR | High |
Highest vs lowest selenium exposure Breast cancer risk No. of participants: 802 (1 RCT) · Participants in trials with low risk of bias Selenium for preventing cancer (2018) · Cochrane | RR 2.04 [0.44, 9.55] | NR | Moderate |
Highest vs lowest selenium exposure Bladder cancer risk No. of participants: 19,009 (2 RCTs) · Participants in trials with low risk of bias Selenium for preventing cancer (2018) · Cochrane | RR 1.07 [0.76, 1.52] | NR | High |
Highest vs lowest selenium exposure Prostate cancer risk No. of participants: 18,942 (4 RCTs) · Participants in trials with low risk of bias Selenium for preventing cancer (2018) · Cochrane | RR 1.01 [0.9, 1.14] | NR | High |
Highest vs lowest selenium exposure Any cancer risk No. of participants: 76,239 (7 observational studies) · Participants in non experimental cohort studies on selenium and cancer Selenium for preventing cancer (2018) · Cochrane | OR 0.72 [0.55, 0.93] | NR | Very low |
Low‐molecular‐weight heparin (LMWH) vs no LMWH Outcomes ( · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | no estimate extracted | NR | No studies |
Vitamin K antagonist (VKA) vs no VKA All‐cause mortality (up to 3 months) · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | RR 0.99 [0.64, 1.55] | 4 studies · 701 participants | Low |
Vitamin K antagonist (VKA) vs no VKA Symptomatic catheter‐related thrombosis (up to 3 months) · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | RR 0.61 [0.23, 1.64] | 4 studies · 1271 participants | Low |
Vitamin K antagonist (VKA) vs no VKA Symptomatic catheter‐related thrombosis measured as asymptomatic catheter‐related thrombosis (up to 3 months) · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | RR 0.61 [0.27, 1.4] | 2 studies · 384 participants | Very low |
Vitamin K antagonist (VKA) vs no VKA Major bleeding (up to 3 months) · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | RR 7.14 [0.88, 57.78] | 2 studies · 1026 participants | Low |
Vitamin K antagonist (VKA) vs no VKA Minor bleeding (up to 3 months) · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | RR 0.69 [0.38, 1.26] | 2 studies · 1026 participants | Low |
Vitamin K antagonist (VKA) vs no VKA Catheter‐related infection (3 months) · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | RR 1.17 [0.74, 1.85] | 1 study · 88 participants | Low |
Vitamin K antagonist (VKA) vs no VKA Premature CVC removal (3 months) · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | RR 0.82 [0.3, 2.24] | 1 study · 88 participants | Low |
Low‐molecular‐weight heparin (LMWH) vs vitamin K antagonist (VKA) Outcomes ( · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | no estimate extracted | NR | No studies |
Low‐molecular‐weight heparin (LMWH) vs vitamin K antagonist (VKA) All‐cause mortality (up to 3 months) · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | RR 0.94 [0.56, 1.59] | 3 studies · 561 participants | Low |
Low‐molecular‐weight heparin (LMWH) vs vitamin K antagonist (VKA) Symptomatic catheter‐related thrombosis (up to 3 months) · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | RR 1.83 [0.44, 7.61] | 2 studies · 327 participants | Very low |
Low‐molecular‐weight heparin (LMWH) vs no LMWH All‐cause mortality (up to 3 months) · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | RR 0.82 [0.53, 1.26] | 5 studies · 1236 participants | Low |
Low‐molecular‐weight heparin (LMWH) vs vitamin K antagonist (VKA) Symptomatic catheter‐related thrombosis measured as asymptomatic catheter‐related thrombosis (up to 3 months) · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | RR 1.61 [0.75, 3.46] | 2 studies · 317 participants | Very low |
Low‐molecular‐weight heparin (LMWH) vs vitamin K antagonist (VKA) Pulmonary embolism (up to 3 months) · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | RR 1.7 [0.74, 3.92] | 2 studies · 327 participants | Low |
Low‐molecular‐weight heparin (LMWH) vs vitamin K antagonist (VKA) Major bleeding (up to 3 months) · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | RR 3.11 [0.13, 73.11] | 2 studies · 289 participants | Very low |
Low‐molecular‐weight heparin (LMWH) vs vitamin K antagonist (VKA) Minor bleeding (up to 3 months) · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | RR 0.95 [0.2, 4.61] | 1 study · 234 participants | Very low |
Low‐molecular‐weight heparin (LMWH) vs vitamin K antagonist (VKA) Thrombocytopenia (up to 3 months)n · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | RR 1.69 [1.2, 2.39] | 2 studies · 327 participants | Moderate |
Low‐molecular‐weight heparin (LMWH) vs no LMWH Symptomatic catheter‐related thrombosis (up to 3 months) · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | RR 0.43 [0.22, 0.81] | 5 studies · 1089 participants | Moderate |
Low‐molecular‐weight heparin (LMWH) vs no LMWH Symptomatic catheter‐related thrombosis measured as asymptomatic catheter‐related thrombosis (up to 3 months) · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | RR 0.95 [0.62, 1.46] | 5 studies · 1089 participants | Very low |
Low‐molecular‐weight heparin (LMWH) vs no LMWH Major bleeding (up to 3 months) · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | RR 1.49 [0.06, 36.28] | 4 studies · 1018 participants | Very low |
Low‐molecular‐weight heparin (LMWH) vs no LMWH Minor bleeding (up to 3 months) · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | RR 1.35 [0.62, 2.92] | 2 studies · 544 participants | Low |
Low‐molecular‐weight heparin (LMWH) vs no LMWH Catheter‐related infection (up to 3 months) · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | RR 0.97 [0.52, 1.79] | 2 studies · 474 participants | Low |
Low‐molecular‐weight heparin (LMWH) vs no LMWH Thrombocytopenia (up to 3 months) · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | RR 1.03 [0.8, 1.33] | 4 studies · 1002 participants | Low |
Vitamin K antagonist (VKA) vs no VKA Outcomes ( · people with cancer with thrombosis prophylaxis and central venous catheters Anticoagulation for people with cancer and central venous catheters (2018) · Cochrane | no estimate extracted | NR | No studies |
Low molecular weight heparin secondary prophylaxis vs vitamin K antagonist secondary prophylaxis All‐cause mortality (main analysis ‐ active cancer) · People with cancer with venous thromboembolism Anticoagulation for the long‐term treatment of venous thromboembolism in people with cancer (2018) · Cochrane | RR 0.99 [0.88, 1.12] | 4 studies · 1712 participants | Low |