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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.

Limit to evidence status or GRADE (optional)

2,325 questions in 216 reviews · Airways

current versions
No studies 249 · 10.7%Ungraded 107 · 4.6%Very low 276 · 11.9%Low 751 · 32.3%Moderate 718 · 30.9%High 224 · 9.6%

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.

QuestionEffectEvidenceStatus / GRADE
Antibiotics vs placebo
HRQoL, SGRQ (total score) Scale from: 0 to 100. SGRQ comprises responses to 50 items, 0 being the best possible score and 100 the worst. WMD of · Adults (aged 40 or over) with COPD presenting with 1 or more exacerbations in the previous year. The two larger…
Prophylactic antibiotic therapy for chronic obstructive pulmonary disease (COPD) (2018) · Cochrane
no estimate extracted7 studies · 2237 participantsHigh
Antibiotics vs placebo
All‐cause mortality WMD of · Adults (aged 40 or over) with COPD presenting with 1 or more exacerbations in the previous year. The two larger…
Prophylactic antibiotic therapy for chronic obstructive pulmonary disease (COPD) (2018) · Cochrane
OR 0.87 [0.66, 1.15]6 studies · 3309 participantsModerate
Antibiotics vs placebo
Serious adverse events WMD of · Adults (aged 40 or over) with COPD presenting with 1 or more exacerbations in the previous year. The two larger…
Prophylactic antibiotic therapy for chronic obstructive pulmonary disease (COPD) (2018) · Cochrane
OR 0.88 [0.74, 1.05]9 studies · 2978 participantsModerate
Antibiotics vs placebo
Any adverse event WMD of · Adults (aged 40 or over) with COPD presenting with 1 or more exacerbations in the previous year. The two larger…
Prophylactic antibiotic therapy for chronic obstructive pulmonary disease (COPD) (2018) · Cochrane
OR 1.07 [0.69, 1.67]4 studies · 512 participantsModerate
Antibiotics vs placebo
FEV1 (mL) WMD of · Adults (aged 40 or over) with COPD presenting with 1 or more exacerbations in the previous year. The two larger…
Prophylactic antibiotic therapy for chronic obstructive pulmonary disease (COPD) (2018) · Cochrane
no estimate extracted6 studies · 658 participantsModerate
Antibiotics vs placebo
Treatment failure within 4 weeks ‐ current drugs only · exacerbations of COPD
Antibiotics for exacerbations of chronic obstructive pulmonary disease (2018) · Cochrane
RR 0.72 [0.56, 0.94]7 studies · 1191 participantsLow
Antibiotics vs placebo overall
Adverse events ‐ overall (any adverse events not specified) · exacerbations of COPD
Antibiotics for exacerbations of chronic obstructive pulmonary disease (2018) · Cochrane
OR 1.2 [0.89, 1.63]6 studies · 1544 participantsModerate
Antibiotics vs placebo
All‐cause mortality · exacerbations of COPD
Antibiotics for exacerbations of chronic obstructive pulmonary disease (2018) · Cochrane
OR 1.27 [0.49, 3.3]1 study · 301 participantsLow
Antibiotics vs placebo
Treatment failure within 4 weeks ‐ current drugs only ‐ inpatient · exacerbations of COPD
Antibiotics for exacerbations of chronic obstructive pulmonary disease (2018) · Cochrane
RR 0.65 [0.38, 1.12]4 studies · 576 participantsModerate
Antibiotics vs placebo
Treatment failure within 4 weeks ‐ drugs not currently used ‐ ICU · exacerbations of COPD
Antibiotics for exacerbations of chronic obstructive pulmonary disease (2018) · Cochrane
RR 0.19 [0.08, 0.45]1 study · 93 participantsModerate
Antibiotics vs placebo
Duration of hospital stay (days) ‐ inpatients · exacerbations of COPD
Antibiotics for exacerbations of chronic obstructive pulmonary disease (2018) · Cochrane
no estimate extracted3 studies · 300 participantsHigh
Antibiotics vs placebo
Duration of hospital stay (days) ‐ ICU patients · exacerbations of COPD
Antibiotics for exacerbations of chronic obstructive pulmonary disease (2018) · Cochrane
no estimate extracted1 study · 94 participantsModerate
Antibiotics vs placebo
All‐cause mortality ‐ inpatients · exacerbations of COPD
Antibiotics for exacerbations of chronic obstructive pulmonary disease (2018) · Cochrane
OR 2.48 [0.94, 6.55]2 studies · 214 participantsModerate
Antibiotics vs placebo
All‐cause mortality ‐ ICU patients · exacerbations of COPD
Antibiotics for exacerbations of chronic obstructive pulmonary disease (2018) · Cochrane
OR 0.21 [0.06, 0.72]1 study · 93 participantsModerate
Antibiotics vs placebo overall
Adverse events ‐ diarrhoea · exacerbations of COPD
Antibiotics for exacerbations of chronic obstructive pulmonary disease (2018) · Cochrane
OR 1.68 [0.92, 3.07]5 studies · 1099 participantsModerate
NMES vs usual care (with or without sham NMES)
Peripheral muscle force · COPD
Neuromuscular electrostimulation for adults with chronic obstructive pulmonary disease (2018) · Cochrane
no estimate extracted6 studies · 159 participantsLow
NMES and exercise vs exercise (with or without sham NMES)
Peripheral muscle endurance/fatigability · COPD
Neuromuscular electrostimulation for adults with chronic obstructive pulmonary disease (2018) · Cochrane
no estimate extractedNRNo studies
NMES and exercise vs exercise (with or without sham NMES)
Thigh muscle size · COPD
Neuromuscular electrostimulation for adults with chronic obstructive pulmonary disease (2018) · Cochrane
no estimate extractedNRNo studies
NMES and exercise vs exercise (with or without sham NMES)
Exercise capacity · COPD
Neuromuscular electrostimulation for adults with chronic obstructive pulmonary disease (2018) · Cochrane
no estimate extracted6 studies · 138 participantsVery low
NMES and exercise vs exercise (with or without sham NMES)
Functional performance · COPD
Neuromuscular electrostimulation for adults with chronic obstructive pulmonary disease (2018) · Cochrane
no estimate extracted2 studies · 44 participantsVery low
NMES and exercise vs exercise (with or without sham NMES)
Symptoms of dyspnoea reported on completion of an exercise test · COPD
Neuromuscular electrostimulation for adults with chronic obstructive pulmonary disease (2018) · Cochrane
no estimate extracted2 studies · 44 participantsVery low
NMES and exercise vs exercise (with or without sham NMES)
Health‐related quality of life · COPD
Neuromuscular electrostimulation for adults with chronic obstructive pulmonary disease (2018) · Cochrane
no estimate extracted5 studies · 122 participantsVery low
NMES and exercise vs exercise (with or without sham NMES)
Minor adverse events assessed: related to intervention only (e.g. redness) · COPD
Neuromuscular electrostimulation for adults with chronic obstructive pulmonary disease (2018) · Cochrane
no estimate extracted6 studies · 144 participantsLow
NMES vs usual care (with or without sham NMES)
Peripheral muscle endurance/fatigability · COPD
Neuromuscular electrostimulation for adults with chronic obstructive pulmonary disease (2018) · Cochrane
no estimate extracted2 studies · 35 participantsLow
NMES vs usual care (with or without sham NMES)
Thigh muscle size · COPD
Neuromuscular electrostimulation for adults with chronic obstructive pulmonary disease (2018) · Cochrane
no estimate extracted4 studies · 124 participantsLow
NMES vs usual care (with or without sham NMES)
Exercise capacity · COPD
Neuromuscular electrostimulation for adults with chronic obstructive pulmonary disease (2018) · Cochrane
no estimate extracted2 studies · 72 participantsLow
NMES vs usual care (with or without sham NMES)
Functional performance · COPD
Neuromuscular electrostimulation for adults with chronic obstructive pulmonary disease (2018) · Cochrane
no estimate extractedNRNo studies
NMES vs usual care (with or without sham NMES)
Symptoms of dyspnoea reported on completion of an exercise test · COPD
Neuromuscular electrostimulation for adults with chronic obstructive pulmonary disease (2018) · Cochrane
no estimate extracted3 studies · 55 participantsVery low
NMES vs usual care (with or without sham NMES)
Health‐related quality of life · COPD
Neuromuscular electrostimulation for adults with chronic obstructive pulmonary disease (2018) · Cochrane
no estimate extracted2 studies · 72 participantsVery low
NMES vs usual care (with or without sham NMES)
Minor adverse events assessed: related to intervention only (e.g. redness) · COPD
Neuromuscular electrostimulation for adults with chronic obstructive pulmonary disease (2018) · Cochrane
RD 05 studies · 139 participantsLow
NMES and exercise vs exercise (with or without sham NMES)
Peripheral muscle force · COPD
Neuromuscular electrostimulation for adults with chronic obstructive pulmonary disease (2018) · Cochrane
no estimate extracted4 studies · 84 participantsVery low
Cyclophosphamide vs placebo
Change in lung function (FVC % predicted) · people with connective tissue disease‐associated interstitial lung disease
Cyclophosphamide for connective tissue disease–associated interstitial lung disease (2018) · Cochrane
no estimate extracted2 studies · 182 participantsLow
Cyclophosphamide vs mycophenolate
Adverse events: pneumonia 12‐month · people with connective tissue disease‐associated interstitial lung disease
Cyclophosphamide for connective tissue disease–associated interstitial lung disease (2018) · Cochrane
OR 1.01 [0.48, 2.14]2 studies · 300 participantsLow
Cyclophosphamide vs mycophenolate
Adverse events: anaemia 12‐month · people with connective tissue disease‐associated interstitial lung disease
Cyclophosphamide for connective tissue disease–associated interstitial lung disease (2018) · Cochrane
OR 1.63 [0.65, 4.11]2 studies · 300 participantsLow
Cyclophosphamide vs mycophenolate
Adverse events: thrombocytopenia 12‐month · people with connective tissue disease‐associated interstitial lung disease
Cyclophosphamide for connective tissue disease–associated interstitial lung disease (2018) · Cochrane
RD 0.03 [0, 0.06]2 studies · 300 participantsLow
Cyclophosphamide vs mycophenolate
Health‐related quality of life (HAQ‐DI) · people with connective tissue disease‐associated interstitial lung disease
Cyclophosphamide for connective tissue disease–associated interstitial lung disease (2018) · Cochrane
no estimate extracted1 study · 142 participantsLow
Cyclophosphamide vs mycophenolate
All‐cause mortality 12‐month · people with connective tissue disease‐associated interstitial lung disease
Cyclophosphamide for connective tissue disease–associated interstitial lung disease (2018) · Cochrane
OR 1.6 [0.65, 3.95]2 studies · 187 participantsLow
Cyclophosphamide vs placebo
Change in lung function (diffusing capacity of the lung for carbon monoxide (DLCO) % predicted) · people with connective tissue disease‐associated interstitial lung disease
Cyclophosphamide for connective tissue disease–associated interstitial lung disease (2018) · Cochrane
no estimate extracted2 studies · 182 participantsLow
Cyclophosphamide vs placebo
Adverse events: pneumonia 12‐month · people with connective tissue disease‐associated interstitial lung disease
Cyclophosphamide for connective tissue disease–associated interstitial lung disease (2018) · Cochrane
OR 1.7 [0.55, 5.32]2 studies · 203 participantsLow
Cyclophosphamide vs placebo
Adverse events: haematuria 12‐month · people with connective tissue disease‐associated interstitial lung disease
Cyclophosphamide for connective tissue disease–associated interstitial lung disease (2018) · Cochrane
OR 2.6 [1.12, 6.03]2 studies · 203 participantsLow
Cyclophosphamide vs placebo
Health‐related quality of life (HAQ‐DI) · people with connective tissue disease‐associated interstitial lung disease
Cyclophosphamide for connective tissue disease–associated interstitial lung disease (2018) · Cochrane
no estimate extracted1 study · 158 participantsModerate
Cyclophosphamide vs placebo
All‐cause mortality 12‐month · people with connective tissue disease‐associated interstitial lung disease
Cyclophosphamide for connective tissue disease–associated interstitial lung disease (2018) · Cochrane
OR 0.94 [0.19, 4.77]2 studies · 179 participantsLow
Cyclophosphamide vs mycophenolate
Change in lung function (FVC % predicted) · people with connective tissue disease‐associated interstitial lung disease
Cyclophosphamide for connective tissue disease–associated interstitial lung disease (2018) · Cochrane
no estimate extracted2 studies · 149 participantsLow
Cyclophosphamide vs mycophenolate
Change in lung function (diffusing capacity of the lung for carbon monoxide (DLCO) % predicted) · people with connective tissue disease‐associated interstitial lung disease
Cyclophosphamide for connective tissue disease–associated interstitial lung disease (2018) · Cochrane
no estimate extracted2 studies · 145 participantsLow
Cyclophosphamide vs mycophenolate
Adverse events: leukopenia 12‐month · people with connective tissue disease‐associated interstitial lung disease
Cyclophosphamide for connective tissue disease–associated interstitial lung disease (2018) · Cochrane
OR 6.86 [3.23, 14.58]2 studies · 300 participantsLow
Fixed‐dose combination aclidinium/formoterol vs aclidinium alone
Exacerbations requiring steroids or antibiotics or both: number of participants · people with COPD
Combined aclidinium bromide and long‐acting beta2‐agonist for chronic obstructive pulmonary disease (COPD) (2018) · Cochrane
OR 0.95 [0.71, 1.27]2 studies · 2156 participantsModerate
Fixed‐dose combination aclidinium/formoterol vs formoterol
Non‐fatal serious adverse events · people with COPD
Combined aclidinium bromide and long‐acting beta2‐agonist for chronic obstructive pulmonary disease (COPD) (2018) · Cochrane
OR 1.15 [0.82, 1.61]5 studies · 3140 participantsModerate
Fixed‐dose combination aclidinium/formoterol vs formoterol
Hospital admissions due to exacerbations: number of participants · people with COPD
Combined aclidinium bromide and long‐acting beta2‐agonist for chronic obstructive pulmonary disease (COPD) (2018) · Cochrane
OR 0.76 [0.45, 1.28]3 studies · 2694 participantsModerate
Fixed‐dose combination aclidinium/formoterol vs formoterol
Improvement in symptoms: number of participants with clinically significant improvement: using TDI focal score (≥ 1 unit) · people with COPD
Combined aclidinium bromide and long‐acting beta2‐agonist for chronic obstructive pulmonary disease (COPD) (2018) · Cochrane
OR 1.3 [1.07, 1.56]2 studies · 2010 participantsHigh
Fixed‐dose combination aclidinium/formoterol vs formoterol
Change in lung function: from baseline in trough FEV1 (L) · people with COPD
Combined aclidinium bromide and long‐acting beta2‐agonist for chronic obstructive pulmonary disease (COPD) (2018) · Cochrane
no estimate extracted4 studies · 2411 participantsHigh