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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

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.

Question	Effect	Evidence	Status / GRADE
Intervention NR Serious adverse events · children with chronic asthma Addition of long‐acting beta₂‐agonists to inhaled corticosteroids for chronic asthma in children (2015) · Cochrane	RR 1.17 [0.75, 1.85]	16 studies · 4022 participants	Moderate
Intervention NR Total number of withdrawals · children with chronic asthma Addition of long‐acting beta₂‐agonists to inhaled corticosteroids for chronic asthma in children (2015) · Cochrane	RR 0.8 [0.67, 0.94]	23 studies · 4374 participants	Low
Intervention NR Change in FEV1 (L) at endpoint · children with chronic asthma Addition of long‐acting beta₂‐agonists to inhaled corticosteroids for chronic asthma in children (2015) · Cochrane	no estimate extracted	9 studies · 1942 participants	Low
Intervention NR Change in morning PEF (L/min) at endpoint · children with chronic asthma Addition of long‐acting beta₂‐agonists to inhaled corticosteroids for chronic asthma in children (2015) · Cochrane	no estimate extracted	16 studies · 3934 participants	Moderate
Intervention NR Total number of adverse events · children with chronic asthma Addition of long‐acting beta₂‐agonists to inhaled corticosteroids for chronic asthma in children (2015) · Cochrane	RR 1.04 [0.98, 1.1]	15 studies · 3284 participants	Moderate
Intervention NR Number of participants with exacerbations requiring systemic steroids · children with chronic asthma Addition of long‐acting beta₂‐agonists to inhaled corticosteroids for chronic asthma in children (2015) · Cochrane	RR 1.69 [0.85, 3.32]	3 studies · 581 participants	Moderate
Intervention NR Number of participants with exacerbations requiring hospitalisation · children with chronic asthma Addition of long‐acting beta₂‐agonists to inhaled corticosteroids for chronic asthma in children (2015) · Cochrane	RR 1.9 [0.65, 5.54]	4 studies · 1008 participants	Moderate
Maintenance LTRA vs placebo Number of participants experiencing one or more episode requiring treatment with oral steroids · episodic viral wheeze in children Leukotriene receptor antagonists as maintenance and intermittent therapy for episodic viral wheeze in children (2015) · Cochrane	OR 1.2 [0.7, 2.06]	1 study · 347 participants	Moderate
Intermittent LTRA vs placebo Serious adverse events · episodic viral wheeze in children Leukotriene receptor antagonists as maintenance and intermittent therapy for episodic viral wheeze in children (2015) · Cochrane	no estimate extracted	NR	No studies
Maintenance LTRA vs placebo Number of participants experiencing one or more episodes requiring ED visit · episodic viral wheeze in children Leukotriene receptor antagonists as maintenance and intermittent therapy for episodic viral wheeze in children (2015) · Cochrane	OR 0.66 [0.37, 1.2]	1 study · 347 participants	Moderate
Maintenance LTRA vs placebo Number of participants experiencing one or more episodes requiring hospital admission · episodic viral wheeze in children Leukotriene receptor antagonists as maintenance and intermittent therapy for episodic viral wheeze in children (2015) · Cochrane	OR 0.65 [0.23, 1.87]	1 study · 347 participants	Moderate
Maintenance LTRA vs placebo Withdrawals ‐ Total number of withdrawals · episodic viral wheeze in children Leukotriene receptor antagonists as maintenance and intermittent therapy for episodic viral wheeze in children (2015) · Cochrane	OR 0.87 [0.66, 1.13]	2 studies · 1729 participants	Moderate
Maintenance LTRA vs placebo Serious adverse events · episodic viral wheeze in children Leukotriene receptor antagonists as maintenance and intermittent therapy for episodic viral wheeze in children (2015) · Cochrane	no estimate extracted	NR	No studies
Intermittent LTRA vs placebo Number of participants experiencing one or more episode requiring treatment with oral steroids · episodic viral wheeze in children Leukotriene receptor antagonists as maintenance and intermittent therapy for episodic viral wheeze in children (2015) · Cochrane	RR 0.85 [0.64, 1.14]	2 studies · 343 participants	Moderate
Intermittent LTRA vs placebo Number of participants experiencing one or more episodes requiring ED visit · episodic viral wheeze in children Leukotriene receptor antagonists as maintenance and intermittent therapy for episodic viral wheeze in children (2015) · Cochrane	OR 1 [0.49, 2.02]	1 study · 141 participants	Moderate
Intermittent LTRA vs placebo Number of participants experiencing one or more episodes requiring hospital admission · episodic viral wheeze in children Leukotriene receptor antagonists as maintenance and intermittent therapy for episodic viral wheeze in children (2015) · Cochrane	OR 0.73 [0.2, 2.73]	1 study · 141 participants	Moderate
Intermittent LTRA vs placebo Withdrawals ‐ Total number of withdrawals · episodic viral wheeze in children Leukotriene receptor antagonists as maintenance and intermittent therapy for episodic viral wheeze in children (2015) · Cochrane	OR 1.03 [0.79, 1.35]	2 studies · 1402 participants	Moderate
Intervention NR Number of exacerbations of bronchiectasis Frequency of acute exacerbations of bronchiectasis · individuals with stable bronchiectasis Airway clearance techniques for bronchiectasis (2015) · Cochrane	RR 0.71 [0.23, 2.25]	1 study · 20 participants	Low
Intervention NR Hospitalisations · individuals with stable bronchiectasis Airway clearance techniques for bronchiectasis (2015) · Cochrane	no estimate extracted	NR	No studies
Intervention NR Health‐related quality of life (disease‐specific) Scale from 0 to 100; lower score indicates better HRQoL. SGRQ total score consists of weighted scores from 3 domains · individuals with stable bronchiectasis Airway clearance techniques for bronchiectasis (2015) · Cochrane	no estimate extracted	1 study · 20 participants	Low
Intervention NR Health‐related quality of life (cough‐specific) Leicester Cough Questionnaire Scale from 0 to 133; higher score indicates better HRQoL. Contains 19 questions from 3 domains on a Likert scale · individuals with stable bronchiectasis Airway clearance techniques for bronchiectasis (2015) · Cochrane	no estimate extracted	1 study · 20 participants	Low
Intervention NR Health‐related quality of life (health status) COPD Assessment Tool. Scale from 0 to 5; higher score indicates worse HRQoL Contains 10 questions with 5‐point Likert scale · individuals with stable bronchiectasis Airway clearance techniques for bronchiectasis (2015) · Cochrane	no estimate extracted	1 study · 30 participants	Low
Intervention NR Respiratory symptoms (symptoms) Breathlessness, Cough and Sputum Scale Scale from 0 to 12. Lower score indicates fewer symptoms · individuals with stable bronchiectasis Airway clearance techniques for bronchiectasis (2015) · Cochrane	no estimate extracted	1 study · 30 participants	Low
Intervention NR Adverse events (AEs) · individuals with stable bronchiectasis Airway clearance techniques for bronchiectasis (2015) · Cochrane	no estimate extracted	NR	No studies
Long‐acting beta2‐agonist plus tiotropium vs tiotropium alone Change in quality of life · addition to tiotropium versus either tiotropium or LABA alone for chronic obstructive pulmonary disease Long‐acting beta₂‐agonist in addition to tiotropium versus either tiotropium or long‐acting beta₂‐agonist… (2015) · Cochrane	no estimate extracted	5 studies · 6709 participants	Moderate
Long‐acting beta2‐agonist plus tiotropium vs long‐acting beta2‐agonist alone Hospital admission (exacerbation) · addition to tiotropium versus either tiotropium or long‐acting beta2‐agonist alone for chronic obstructive pulmonary… Long‐acting beta₂‐agonist in addition to tiotropium versus either tiotropium or long‐acting beta₂‐agonist… (2015) · Cochrane	OR 0.9 [0.66, 1.22]	3 studies · 3514 participants	Low
Long‐acting beta2‐agonist plus tiotropium vs long‐acting beta2‐agonist alone Mortality (all cause) · addition to tiotropium versus either tiotropium or long‐acting beta2‐agonist alone for chronic obstructive pulmonary… Long‐acting beta₂‐agonist in addition to tiotropium versus either tiotropium or long‐acting beta₂‐agonist… (2015) · Cochrane	OR 1.15 [0.62, 2.13]	3 studies · 3514 participants	Low
Long‐acting beta2‐agonist plus tiotropium vs long‐acting beta2‐agonist alone Change in trough FEV1 (L) · addition to tiotropium versus either tiotropium or long‐acting beta2‐agonist alone for chronic obstructive pulmonary… Long‐acting beta₂‐agonist in addition to tiotropium versus either tiotropium or long‐acting beta₂‐agonist… (2015) · Cochrane	no estimate extracted	4 studies · 3513 participants	High
Long‐acting beta2‐agonist plus tiotropium vs tiotropium alone Quality of life SGRQ responder analysis at 6 months · addition to tiotropium versus either tiotropium or LABA alone for chronic obstructive pulmonary disease Long‐acting beta₂‐agonist in addition to tiotropium versus either tiotropium or long‐acting beta₂‐agonist… (2015) · Cochrane	OR 1.32 [1.19, 1.46]	3 studies · 5978 participants	Moderate
Long‐acting beta2‐agonist plus tiotropium vs tiotropium alone Hospital admission (all cause) · addition to tiotropium versus either tiotropium or LABA alone for chronic obstructive pulmonary disease Long‐acting beta₂‐agonist in addition to tiotropium versus either tiotropium or long‐acting beta₂‐agonist… (2015) · Cochrane	OR 1.01 [0.86, 1.19]	4 studies · 4856 participants	Moderate
Long‐acting beta2‐agonist plus tiotropium vs tiotropium alone Hospital admission (exacerbation) · addition to tiotropium versus either tiotropium or LABA alone for chronic obstructive pulmonary disease Long‐acting beta₂‐agonist in addition to tiotropium versus either tiotropium or long‐acting beta₂‐agonist… (2015) · Cochrane	OR 1.02 [0.8, 1.28]	4 studies · 4856 participants	Low
Long‐acting beta2‐agonist plus tiotropium vs tiotropium alone Mortality (all cause) · addition to tiotropium versus either tiotropium or LABA alone for chronic obstructive pulmonary disease Long‐acting beta₂‐agonist in addition to tiotropium versus either tiotropium or long‐acting beta₂‐agonist… (2015) · Cochrane	OR 1.24 [0.81, 1.9]	8 studies · 9633 participants	Low
Long‐acting beta2‐agonist plus tiotropium vs tiotropium alone Change in trough FEV1 (L) · addition to tiotropium versus either tiotropium or LABA alone for chronic obstructive pulmonary disease Long‐acting beta₂‐agonist in addition to tiotropium versus either tiotropium or long‐acting beta₂‐agonist… (2015) · Cochrane	no estimate extracted	10 studies · 9573 participants	High
Long‐acting beta2‐agonist plus tiotropium vs long‐acting beta2‐agonist alone Change in quality of life · addition to tiotropium versus either tiotropium or long‐acting beta2‐agonist alone for chronic obstructive pulmonary… Long‐acting beta₂‐agonist in addition to tiotropium versus either tiotropium or long‐acting beta₂‐agonist… (2015) · Cochrane	no estimate extracted	4 studies · 3378 participants	Moderate
Long‐acting beta2‐agonist plus tiotropium vs long‐acting beta2‐agonist alone Quality of life SGRQ responder analysis at 6 months · addition to tiotropium versus either tiotropium or long‐acting beta2‐agonist alone for chronic obstructive pulmonary… Long‐acting beta₂‐agonist in addition to tiotropium versus either tiotropium or long‐acting beta₂‐agonist… (2015) · Cochrane	OR 1.53 [1.31, 1.79]	2 studies · 2923 participants	Moderate
Long‐acting beta2‐agonist plus tiotropium vs long‐acting beta2‐agonist alone Hospital admission (all cause) · addition to tiotropium versus either tiotropium or long‐acting beta2‐agonist alone for chronic obstructive pulmonary… Long‐acting beta₂‐agonist in addition to tiotropium versus either tiotropium or long‐acting beta₂‐agonist… (2015) · Cochrane	OR 0.93 [0.76, 1.14]	3 studies · 3514 participants	Moderate
Tiotropium vs ipratropium Change in baseline trough FEV1 · chronic obstructive pulmonary disease (COPD). Participants in included studies had an average baseline FEV1 of around… Tiotropium versus ipratropium bromide for chronic obstructive pulmonary disease (2015) · Cochrane	no estimate extracted	2 studies · 1073 participants	Moderate
Tiotropium vs ipratropium All‐cause serious adverse events · chronic obstructive pulmonary disease (COPD). Participants in included studies had an average baseline FEV1 of around… Tiotropium versus ipratropium bromide for chronic obstructive pulmonary disease (2015) · Cochrane	OR 0.5 [0.34, 0.73]	2 studies · 1073 participants	High
Tiotropium vs ipratropium Hospital admissions (all‐cause) · chronic obstructive pulmonary disease (COPD). Participants in included studies had an average baseline FEV1 of around… Tiotropium versus ipratropium bromide for chronic obstructive pulmonary disease (2015) · Cochrane	OR 0.34 [0.15, 0.76]	1 study · 538 participants	Moderate
Tiotropium vs ipratropium Mortality (all‐cause) · chronic obstructive pulmonary disease (COPD). Participants in included studies had an average baseline FEV1 of around… Tiotropium versus ipratropium bromide for chronic obstructive pulmonary disease (2015) · Cochrane	OR 1.39 [0.44, 4.39]	2 studies · 1073 participants	Moderate
Tiotropium vs ipratropium Quality of life ( · chronic obstructive pulmonary disease (COPD). Participants in included studies had an average baseline FEV1 of around… Tiotropium versus ipratropium bromide for chronic obstructive pulmonary disease (2015) · Cochrane	no estimate extracted	1 study · 535 participants	Moderate
Tiotropium vs ipratropium Patients with one or more exacerbations · chronic obstructive pulmonary disease (COPD). Participants in included studies had an average baseline FEV1 of around… Tiotropium versus ipratropium bromide for chronic obstructive pulmonary disease (2015) · Cochrane	OR 0.71 [0.52, 0.95]	2 studies · 1073 participants	High
Tiotropium vs ipratropium Withdrawals · chronic obstructive pulmonary disease (COPD). Participants in included studies had an average baseline FEV1 of around… Tiotropium versus ipratropium bromide for chronic obstructive pulmonary disease (2015) · Cochrane	OR 0.58 [0.41, 0.83]	2 studies · 1073 participants	High
Intervention NR Exercise capacity · patients with pulmonary hypertension secondary to systemic scleroderma. Calcium channel blockers for pulmonary arterial hypertension (2015) · Cochrane	no estimate extracted	67 participants	Very low
Intervention NR WHO/NYHA functional class · patients with pulmonary hypertension secondary to systemic scleroderma. Calcium channel blockers for pulmonary arterial hypertension (2015) · Cochrane	no estimate extracted	NR	Very low
Indacaterol vs placebo End‐of‐study trough FEV1 mL · people with COPD Indacaterol, a once‐daily beta₂‐agonist, versus twice‐daily beta₂‐agonists or placebo for chronic… (2015) · Cochrane	no estimate extracted	10 studies · 5001 participants	High
Indacaterol vs twice‐daily long‐acting beta2‐agonists Number of participants experiencing at least 1 exacerbation Exacerbations · patients with chronic obstructive pulmonary disease Indacaterol, a once‐daily beta₂‐agonist, versus twice‐daily beta₂‐agonists or placebo for chronic… (2015) · Cochrane	OR 1.07 [0.86, 1.33]	2 studies · 1869 participants	Moderate
Indacaterol vs twice‐daily long‐acting beta2‐agonists Serious adverse events Adverse events · patients with chronic obstructive pulmonary disease Indacaterol, a once‐daily beta₂‐agonist, versus twice‐daily beta₂‐agonists or placebo for chronic… (2015) · Cochrane	OR 1.02 [0.79, 1.32]	4 studies · 3266 participants	Moderate
Indacaterol vs twice‐daily long‐acting beta2‐agonists Mortality Deaths · patients with chronic obstructive pulmonary disease Indacaterol, a once‐daily beta₂‐agonist, versus twice‐daily beta₂‐agonists or placebo for chronic… (2015) · Cochrane	OR 1 [0.31, 3.28]	4 studies · 3266 participants	Moderate
Indacaterol vs placebo Number of participants with a clinically significant improvement in QOL SGRQ · people with COPD Indacaterol, a once‐daily beta₂‐agonist, versus twice‐daily beta₂‐agonists or placebo for chronic… (2015) · Cochrane	OR 1.64	9 studies · 4906 participants	High