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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.
15,213 questions in 2,394 reviews
current versionsNo studies 15,213 · 100%Ungraded 0 · 0%Very low 0 · 0%Low 0 · 0%Moderate 0 · 0%High 0 · 0%
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 |
|---|---|---|---|
Surgery plus radiotherapy vs Radiotherapy alone Locoregional recurrence · Adults with oral cavity or oropharyngeal cancer Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Locoregional recurrence: not reported. | 0 studies | No studies |
CAD/CAM nitinol fixed (bonded) retainer vs Conventional/analogue multistrand fixed (bonded) retainer Patient satisfaction: discomfort/pain (lower arch) · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | No studies measured or reported this outcome | 0 studies | No studies |
Light vibrational forces (LVF) vs Conventional orthodontic appliance treatment (placebo or no adjunct) Cost of treatment · Adolescents and adults with malocclusion undergoing orthodontic treatment with fixed or removable appliances Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | Cost of treatment was not investigated in any of the included studies. | NR | No studies |
Hawley removable retainer vs Clear plastic removable retainer Adverse effects on oral health · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | Not measured | 0 studies | No studies |
Surgery plus radiotherapy vs Radiotherapy alone Disease-free survival · Adults with oral cavity or oropharyngeal cancer Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Disease-free survival: not reported. | 0 studies | No studies |
Full-time wear of removable retainer (any type) vs Part-time wear of removable retainer (any type) Survival of retainers · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | Not measured | 0 studies | No studies |
Full-time wear of removable retainer (any type) vs Part-time wear of removable retainer (any type) Adverse effects on oral health · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | Not measured | 0 studies | No studies |
Fibre-reinforced composite fixed (bonded) retainer vs Multistrand / spiral wire fixed (bonded) retainer Adverse effects on oral health: bleeding on probing (lower arch) · People who had received fixed appliance orthodontic treatment · 12 months, lower arch Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | No RCTs at 12-month follow-up; 1 RCT at 6 months found no difference (very low-certainty) | 0 studies | No studies |
Hawley removable retainer vs Clear plastic removable retainer Patient satisfaction: comfort (VAS, upper and lower arches) · People who had received fixed appliance orthodontic treatment · 12 months, upper and lower arches Retention procedures for stabilising tooth position after treatment with orthodontic braces (2023) · Cochrane | No RCTs at 12 months; 1 RCT at 6 months: Hawley less comfortable (VAS MD -1.86, 95% CI -2.19 to -1.53; very low-certainty) | 0 studies | No studies |
Low level laser therapy (LLLT) vs Conventional orthodontic appliance treatment Patient-reported need for analgesics · Adolescents and adults with malocclusion undergoing fixed orthodontic appliance treatment Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | Patient-reported need for analgesics | Not reported | NR | No studies |
Low level laser therapy (LLLT) vs Conventional orthodontic appliance treatment Total number of orthodontic appliance adjustment visits during overall treatment · Adolescents and adults with malocclusion undergoing fixed orthodontic appliance treatment Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | No study reported on the influence of LLLT on the total number of orthodontic appliance adjustment visits to complete a course of treatment. | NR | No studies |
Elective radical (comprehensive) neck dissection vs Elective selective neck dissection Locoregional recurrence · Adults with oral cavity cancer Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Locoregional recurrence: not reported. | 0 studies | No studies |
Surgery vs Radiotherapy alone Locoregional recurrence · Adults with oropharyngeal cancer Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Locoregional recurrence: not reported. | 0 studies | No studies |
Surgery plus radiotherapy vs Radiotherapy alone Recurrence · Adults with oral cavity or oropharyngeal cancer Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Recurrence: not reported. | 0 studies | No studies |
Low level laser therapy (LLLT) vs Conventional orthodontic appliance treatment Duration of total overall orthodontic treatment · Adolescents and adults with malocclusion undergoing fixed orthodontic appliance treatment Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | No study reported on the influence of LLLT on the total overall orthodontic treatment duration. | NR | No studies |
Light-emitting diode (LED) photobiomodulation vs Conventional orthodontic appliance treatment Orthodontic tooth movement (OTM) during alignment stage · Adolescents and adults with malocclusion undergoing fixed orthodontic appliance treatment Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | Orthodontic tooth movement (OTM) during alignment stage | Not reported | NR | No studies |
Light-emitting diode (LED) photobiomodulation vs Conventional orthodontic appliance treatment Patient-reported need for analgesics · Adolescents and adults with malocclusion undergoing fixed orthodontic appliance treatment Non‐surgical adjunctive interventions for accelerating tooth movement in patients undergoing orthodontic… (2023) · Cochrane | Patient-reported need for analgesics | Not reported | NR | No studies |
Surgery plus adjuvant radiotherapy vs Chemotherapy (chemoradiotherapy) Adverse events associated with treatment · Adults with oral cavity or oropharyngeal cancer Interventions for the treatment of oral cavity and oropharyngeal cancers: surgical treatment (2023) · Cochrane | Adverse events: not reported for any participants (Iyer 2015). | 0 studies | No studies |
Lutein with or without zeaxanthin vs placebo Resource use and costs · people with AMD Antioxidant vitamin and mineral supplements for slowing the progression of age‐related macular degeneration (2023) · Cochrane | no estimate extracted | NR | No studies |
Vitamin E vs placebo Progression to neovascular AMD · people with AMD Antioxidant vitamin and mineral supplements for slowing the progression of age‐related macular degeneration (2023) · Cochrane | no estimate extracted | NR | No studies |
Vitamin E vs placebo Progression to geographic atrophy · people with AMD Antioxidant vitamin and mineral supplements for slowing the progression of age‐related macular degeneration (2023) · Cochrane | no estimate extracted | NR | No studies |
Vitamin E vs placebo Quality of life · people with AMD Antioxidant vitamin and mineral supplements for slowing the progression of age‐related macular degeneration (2023) · Cochrane | no estimate extracted | NR | No studies |
Vitamin E vs placebo Resource use and costs · people with AMD Antioxidant vitamin and mineral supplements for slowing the progression of age‐related macular degeneration (2023) · Cochrane | no estimate extracted | NR | No studies |
Zinc vs placebo Quality of life · people with AMD Antioxidant vitamin and mineral supplements for slowing the progression of age‐related macular degeneration (2023) · Cochrane | no estimate extracted | NR | No studies |
Zinc vs placebo Resource use and costs · people with AMD Antioxidant vitamin and mineral supplements for slowing the progression of age‐related macular degeneration (2023) · Cochrane | no estimate extracted | NR | No studies |
Antioxidant multivitamin and mineral supplement vs placebo or no treatment Resource use and costs · people with AMD Antioxidant vitamin and mineral supplements for slowing the progression of age‐related macular degeneration (2023) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings table ‐ Planned hospital birth vs Planned home birth Maternal mortality ‐ not reported · Pregnant women at low risk of complications Planned hospital birth compared with planned home birth for pregnant women at low risk of complications (2023) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings table ‐ Planned hospital birth vs Planned home birth Perinatal mortality ‐ not reported · Pregnant women at low risk of complications Planned hospital birth compared with planned home birth for pregnant women at low risk of complications (2023) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings table ‐ Planned hospital birth vs Planned home birth Apgar < 7 at 5 min ‐ not reported · Pregnant women at low risk of complications Planned hospital birth compared with planned home birth for pregnant women at low risk of complications (2023) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings table ‐ Planned hospital birth vs Planned home birth Transfer to neonatal intensive care unit ‐ not reported · Pregnant women at low risk of complications Planned hospital birth compared with planned home birth for pregnant women at low risk of complications (2023) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings table ‐ Planned hospital birth vs Planned home birth Maternal satisfaction ‐ not reported · Pregnant women at low risk of complications Planned hospital birth compared with planned home birth for pregnant women at low risk of complications (2023) · Cochrane | no estimate extracted | NR | No studies |
Antibiotics vs placebo Cost‐effectiveness of treatment · Participants with acute bacterial conjunctivitis Antibiotics versus placebo for acute bacterial conjunctivitis (2023) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings for airway clearance techniques vs no airway clearance techniques Exacerbation rate (number of exacerbations/year) · children and adults with cystic fibrosis Airway clearance techniques compared to no airway clearance techniques for cystic fibrosis (2023) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings for airway clearance techniques vs no airway clearance techniques Exercise tolerance (MSWT) · children and adults with cystic fibrosis Airway clearance techniques compared to no airway clearance techniques for cystic fibrosis (2023) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings for airway clearance techniques vs no airway clearance techniques Well‐being or QoL · children and adults with cystic fibrosis Airway clearance techniques compared to no airway clearance techniques for cystic fibrosis (2023) · Cochrane | no estimate extracted | NR | No studies |
Hypertonic saline 3% to 7% vs isotonic saline LCI · adults and children with cystic fibrosis (during acute exacerbations of lung disease) Nebulised hypertonic saline for cystic fibrosis (2023) · Cochrane | no estimate extracted | NR | No studies |
Hypertonic saline 3% to 7% vs isotonic saline Measures of sputum clearance · adults and children with cystic fibrosis (during acute exacerbations of lung disease) Nebulised hypertonic saline for cystic fibrosis (2023) · Cochrane | no estimate extracted | NR | No studies |
Hypertonic saline vs rhDNase with LCI · adults and children with cystic fibrosis Nebulised hypertonic saline for cystic fibrosis (2023) · Cochrane | no estimate extracted | NR | No studies |
Hypertonic saline vs rhDNase with Mortality · adults and children with cystic fibrosis Nebulised hypertonic saline for cystic fibrosis (2023) · Cochrane | no estimate extracted | NR | No studies |
Hypertonic saline vs rhDNase with Measures of sputum clearance · adults and children with cystic fibrosis Nebulised hypertonic saline for cystic fibrosis (2023) · Cochrane | no estimate extracted | NR | No studies |
Hypertonic saline vs amiloride FEV1: change from baseline, short‐term · adults and children with cystic fibrosis Nebulised hypertonic saline for cystic fibrosis (2023) · Cochrane | no estimate extracted | NR | No studies |
Hypertonic saline vs amiloride FEV1: change from baseline, long‐term · adults and children with cystic fibrosis Nebulised hypertonic saline for cystic fibrosis (2023) · Cochrane | no estimate extracted | NR | No studies |
Hypertonic saline vs amiloride LCI · adults and children with cystic fibrosis Nebulised hypertonic saline for cystic fibrosis (2023) · Cochrane | no estimate extracted | NR | No studies |
Hypertonic saline vs amiloride Mortality · adults and children with cystic fibrosis Nebulised hypertonic saline for cystic fibrosis (2023) · Cochrane | no estimate extracted | NR | No studies |
Hypertonic saline vs amiloride Pulmonary exacerbations · adults and children with cystic fibrosis Nebulised hypertonic saline for cystic fibrosis (2023) · Cochrane | no estimate extracted | NR | No studies |
Hypertonic saline vs amiloride Adverse events · adults and children with cystic fibrosis Nebulised hypertonic saline for cystic fibrosis (2023) · Cochrane | no estimate extracted | NR | No studies |
Hypertonic saline vs sodium‐2‐mercaptoethane sulphonate (Mistabron®) FEV1: short‐term · adults and children with cystic fibrosis Nebulised hypertonic saline for cystic fibrosis (2023) · Cochrane | no estimate extracted | NR | No studies |
Hypertonic saline vs sodium‐2‐mercaptoethane sulphonate (Mistabron®) FEV1: long‐term · adults and children with cystic fibrosis Nebulised hypertonic saline for cystic fibrosis (2023) · Cochrane | no estimate extracted | NR | No studies |
Hypertonic saline vs sodium‐2‐mercaptoethane sulphonate (Mistabron®) LCI · adults and children with cystic fibrosis Nebulised hypertonic saline for cystic fibrosis (2023) · Cochrane | no estimate extracted | NR | No studies |
Hypertonic saline vs sodium‐2‐mercaptoethane sulphonate (Mistabron®) Mortality · adults and children with cystic fibrosis Nebulised hypertonic saline for cystic fibrosis (2023) · Cochrane | no estimate extracted | NR | No studies |