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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 |
|---|---|---|---|
Minimal incision palatopharyngoplasty (MIPP) vs MIPP with additional individualised velopharyngeal surgery (pharyngeal flap or sphincter pharyngoplasty) Instrumental assessment: nasalance score (nasometry and pressure-flow measure) · Children or adolescents aged 3 years or older with velopharyngeal insufficiency (VPI) associated with non-syndromic… Interventions for the management of submucous cleft palate (2008) · Cochrane | Nasalance score by nasometry and pressure-flow measure: the single included trial (Ysunza 2001) provided no data for this outcome. | 0 studies | No studies |
Occlusal adjustment as an adjunct to non-surgical periodontal therapy vs Non-surgical periodontal therapy alone (no occlusal adjustment) Patient acceptability of treatment and its side effects · Adults (aged 18 years or older) with a clinical diagnosis of (chronic) periodontitis · Minimum 3 months (planned) Occlusal interventions for periodontitis in adults (2008) · Cochrane | no estimate extracted | 0 studies | No studies |
Systemic oral acyclovir vs Placebo or no treatment Direct costs (medication, hospital bed days) · Children and young adults under 25 years with primary herpetic gingivostomatitis (with or without herpes labialis) Acyclovir for treating primary herpetic gingivostomatitis (2008) · Cochrane | No data available in either included study. | NR | No studies |
Minimal incision palatopharyngoplasty (MIPP) vs MIPP with additional individualised velopharyngeal surgery (pharyngeal flap or sphincter pharyngoplasty) Self-esteem (validated questionnaires) · Children or adolescents aged 3 years or older with velopharyngeal insufficiency (VPI) associated with non-syndromic… Interventions for the management of submucous cleft palate (2008) · Cochrane | No data were available for this patient-reported outcome in the single included trial. | 0 studies | No studies |
Occlusal adjustment as an adjunct to surgical periodontal therapy vs Surgical periodontal therapy alone (no occlusal adjustment) Tooth loss · Adults (aged 18 years or older) with a clinical diagnosis of (chronic) periodontitis · Minimum 3 months (planned) Occlusal interventions for periodontitis in adults (2008) · Cochrane | no estimate extracted | 0 studies | No studies |
Hand instrumentation in conjunction with (as an adjunct to) an ultrasonic device designed specifically for root canal treatment and capable of the active or passive removal of dentine within the root canal vs Hand instrumentation used alone (files and reamers used manually) Outcome NR · People over 18 years of age with single or multiple permanent teeth with a completely formed apex and no evidence of… Hand and ultrasonic instrumentation for orthograde root canal treatment of permanent teeth (2008) · Cochrane | No eligible randomised controlled trials were identified. | NR | No studies |
Occlusal adjustment as an adjunct to non-surgical periodontal therapy vs Non-surgical periodontal therapy alone (no occlusal adjustment) Tooth loss · Adults (aged 18 years or older) with a clinical diagnosis of (chronic) periodontitis · Minimum 3 months (planned) Occlusal interventions for periodontitis in adults (2008) · Cochrane | no estimate extracted | 0 studies | No studies |
procaine vs placebo overall changes from baseline in "healthy persons7 ‐ not measured · "healthy" old persons and demented women Procaine treatments for cognition and dementia (2008) · Cochrane | no estimate extracted | NR | No studies |
AFI vs SDVP: summary of findings table Perinatal deaths · pregnant women to prevent adverse pregnancy outcome Amniotic fluid index versus single deepest vertical pocket as a screening test for preventing adverse… (2008) · Cochrane | no estimate extracted | NR | No studies |
Intervention NR Morbidity · type 2 diabetes mellitus Dipeptidyl peptidase‐4 (DPP‐4) inhibitors for type 2 diabetes mellitus (2008) · Cochrane | no estimate extracted | NR | No studies |
Intervention NR Health‐related quality of life · type 2 diabetes mellitus Dipeptidyl peptidase‐4 (DPP‐4) inhibitors for type 2 diabetes mellitus (2008) · Cochrane | no estimate extracted | NR | No studies |
Intervention NR Morbidity · patients with type 2 diabetes mellitus Dipeptidyl peptidase‐4 (DPP‐4) inhibitors for type 2 diabetes mellitus (2008) · Cochrane | no estimate extracted | NR | No studies |
Intervention NR Health‐related quality of life · patients with type 2 diabetes mellitus Dipeptidyl peptidase‐4 (DPP‐4) inhibitors for type 2 diabetes mellitus (2008) · Cochrane | no estimate extracted | NR | No studies |
Occlusal adjustment as an adjunct to non-surgical periodontal therapy vs Non-surgical periodontal therapy alone (no occlusal adjustment) Adverse effects (e.g. thermal sensitivity, over-eruption, TMJ symptoms, poor aesthetics, reduced oral hygiene) · Adults (aged 18 years or older) with a clinical diagnosis of (chronic) periodontitis · Minimum 3 months (planned) Occlusal interventions for periodontitis in adults (2008) · Cochrane | no estimate extracted | 0 studies | No studies |
One type of occlusal intervention as an adjunct to periodontal therapy vs A different type of occlusal intervention as an adjunct to periodontal therapy (head-to-head) Outcome NR · Adults (aged 18 years or older) with a clinical diagnosis of (chronic) periodontitis · Minimum 3 months (planned) Occlusal interventions for periodontitis in adults (2008) · Cochrane | no estimate extracted | 0 studies | No studies |
Minimal incision palatopharyngoplasty (MIPP) vs MIPP with additional individualised velopharyngeal surgery (pharyngeal flap or sphincter pharyngoplasty) Adverse effect: unacceptable nasal resonance after repair · Children or adolescents aged 3 years or older with velopharyngeal insufficiency (VPI) associated with non-syndromic… Interventions for the management of submucous cleft palate (2008) · Cochrane | The trial report provided no information on this adverse event; no information on adverse events or serious complications was reported. | 0 studies | No studies |
Occlusal intervention as an adjunct to periodontal therapy vs Sham (placebo) occlusal intervention as an adjunct to periodontal therapy Outcome NR · Adults (aged 18 years or older) with a clinical diagnosis of (chronic) periodontitis · Minimum 3 months (planned) Occlusal interventions for periodontitis in adults (2008) · Cochrane | no estimate extracted | 0 studies | No studies |
Systemic oral acyclovir vs Placebo or no treatment Quality of life (assessed by a validated questionnaire) · Children and young adults under 25 years with primary herpetic gingivostomatitis (with or without herpes labialis) Acyclovir for treating primary herpetic gingivostomatitis (2008) · Cochrane | No data were available in either included study (Amir 1997b; Ducoulombier 1988). | NR | No studies |
Antifungal drugs absorbed from GI tract (fluconazole, ketoconazole, itraconazole) vs Placebo or no treatment Relief of dysphagia · Patients with cancer receiving chemotherapy or radiotherapy or both Interventions for preventing oral candidiasis for patients with cancer receiving treatment (2007) · Cochrane | No trial reported this planned secondary outcome for any comparison in this review | NR | No studies |
Prefabricated metal post and core (Category II) vs Metal custom-cast post and core (Category I) Outcome NR · Participants with permanent endodontically-treated (root-filled) teeth for which a post is indicated to retain the… · Minimum 6 months (planned) Root canal posts for the restoration of root filled teeth (2007) · Cochrane | No included trial compared metal-cast posts with prefabricated metal posts (a planned primary comparison); no eligible study identified. | 0 studies | No studies |
Occlusal splint vs Pharmacological interventions (benzodiazepines, anticonvulsants, beta blockers, dopamine agents, antidepressants, botulinum toxin A and B, analgesics) Outcome NR · People with sleep bruxism (tooth grinding or clenching); children (greater than 1 year old) and adults; diagnosis… Occlusal splints for treating sleep bruxism (tooth grinding) (2007) · Cochrane | Pharmacological interventions remained a planned comparator, but no included trial compared occlusal splint with any drug; no eligible study. | 0 studies | No studies |
Occlusal splint vs Behaviour therapy (sleep hygiene, relaxation, psychotherapy, hypnosis, biofeedback) Outcome NR · People with sleep bruxism (tooth grinding or clenching); children (greater than 1 year old) and adults; diagnosis… Occlusal splints for treating sleep bruxism (tooth grinding) (2007) · Cochrane | Behaviour therapy remained a planned comparator, but no included trial compared occlusal splint with behaviour therapy; no eligible study. | 0 studies | No studies |
Metal post of one alloy type vs Metal post of a different alloy type Outcome NR · Participants with permanent endodontically-treated (root-filled) teeth for which a post is indicated to retain the… · Minimum 6 months (planned) Root canal posts for the restoration of root filled teeth (2007) · Cochrane | No included trial evaluated alloy type in metal posts (a planned secondary comparison); no eligible study identified. | 0 studies | No studies |
Antifungal drugs absorbed from GI tract (fluconazole, ketoconazole, itraconazole) vs Placebo or no treatment Cost of oral care · Patients with cancer receiving chemotherapy or radiotherapy or both Interventions for preventing oral candidiasis for patients with cancer receiving treatment (2007) · Cochrane | No trial reported this planned secondary outcome for any comparison in this review | NR | No studies |
Antifungal drugs absorbed from GI tract (fluconazole, ketoconazole, itraconazole) vs Placebo or no treatment Duration of stay in hospital (days) · Patients with cancer receiving chemotherapy or radiotherapy or both Interventions for preventing oral candidiasis for patients with cancer receiving treatment (2007) · Cochrane | No trial reported this planned secondary outcome for any comparison in this review | NR | No studies |
Occlusal splint vs Placebo Outcome NR · People with sleep bruxism (tooth grinding or clenching); children (greater than 1 year old) and adults; diagnosis… Occlusal splints for treating sleep bruxism (tooth grinding) (2007) · Cochrane | Placebo remained a planned comparator in the review methods (Types of interventions), but none of the five included trials compared occlusal splint with placebo; no eligible study. | 0 studies | No studies |
Antifungal drugs absorbed from GI tract (fluconazole, ketoconazole, itraconazole) vs Placebo or no treatment Patient quality of life · Patients with cancer receiving chemotherapy or radiotherapy or both Interventions for preventing oral candidiasis for patients with cancer receiving treatment (2007) · Cochrane | No trial reported this planned secondary outcome for any comparison in this review | NR | No studies |
Cast post and core with a diaphragm vs Cast post and core without a diaphragm Outcome NR · Participants with permanent endodontically-treated (root-filled) teeth for which a post is indicated to retain the… · Minimum 6 months (planned) Root canal posts for the restoration of root filled teeth (2007) · Cochrane | No included trial evaluated the presence of a diaphragm in cast posts (a planned secondary comparison); no eligible study identified. | 0 studies | No studies |
Antifungal drugs absorbed from GI tract (fluconazole, ketoconazole, itraconazole) vs Placebo or no treatment Amount of analgesia · Patients with cancer receiving chemotherapy or radiotherapy or both Interventions for preventing oral candidiasis for patients with cancer receiving treatment (2007) · Cochrane | No trial reported this planned secondary outcome for any comparison in this review | NR | No studies |
Post and core restoration with a ferrule vs Post and core restoration without a ferrule Outcome NR · Participants with permanent endodontically-treated (root-filled) teeth for which a post is indicated to retain the… · Minimum 6 months (planned) Root canal posts for the restoration of root filled teeth (2007) · Cochrane | No included trial evaluated the presence of a ferrule (a planned secondary comparison); no eligible study identified. | 0 studies | No studies |
Antifungal drugs absorbed from GI tract (fluconazole, ketoconazole, itraconazole) vs Placebo or no treatment Relief of pain · Patients with cancer receiving chemotherapy or radiotherapy or both Interventions for preventing oral candidiasis for patients with cancer receiving treatment (2007) · Cochrane | No trial reported this planned secondary outcome for any comparison in this review | NR | No studies |
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery) Aesthetics (patient's opinion) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | No data were found for this outcome (listed under 'Other outcomes: No data were found for the following outcomes'). | 0 studies | No studies |
Tongue scraping (mechanical tongue cleaning) vs Placebo or no intervention (nothing) Outcome NR · Adults (over 18 years) with a clinical or self-assessed diagnosis of halitosis · Minimum 4 weeks (planned) Tongue scraping for treating halitosis (2006) · Cochrane | No eligible randomized controlled trials comparing tongue scraping with placebo or no intervention were identified. | 0 studies | No studies |
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery) Cost/benefit (treatment time plus estimated material costs) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | No data were found for this outcome (listed under 'Other outcomes: No data were found for the following outcomes'). | 0 studies | No studies |
Tongue scraper or tongue cleaner (One Drop Only tongue cleaner; Tongue-Putzer scraper; polystyrene scraper) vs Toothbrush (used to clean the tongue) Self-expressed (perceived) or organoleptic (human nose) assessment of halitosis · Adults (over 18 years) with a clinical or self-assessed diagnosis of halitosis · Minimum 4 weeks (planned) Tongue scraping for treating halitosis (2006) · Cochrane | Neither of the two included trials provided any self expressed (perceived) or organoleptic (human nose) assessments of halitosis (the review's primary outcomes); no data. | 0 studies | No studies |
Intervention NR MD: Mean difference · Mental health patients Methods of consumer involvement in developing healthcare policy and research, clinical practice guidelines… (2006) · Cochrane | no estimate extracted | NR | No studies |
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery) Disease recurrence (% sites with >=2 mm loss of probing attachment from 12 months after treatment) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | No data were found for this outcome (listed under 'Other outcomes: No data were found for the following outcomes'). | 0 studies | No studies |
Guided tissue regeneration (GTR) with barrier membrane (resorbable or non-resorbable) vs Open flap debridement (access flap surgery) Ease of maintenance (% of sites with <4 mm probing depth) · Patients with chronic periodontitis (aged 21 years or older) with periodontal infra-bony defects; furcation-involved… Guided tissue regeneration for periodontal infra-bony defects (2006) · Cochrane | No data were found for this outcome (listed under 'Other outcomes: No data were found for the following outcomes'). | 0 studies | No studies |
Tongue scraping (mechanical tongue cleaning) vs Mouthwash or other chemical intervention Outcome NR · Adults (over 18 years) with a clinical or self-assessed diagnosis of halitosis · Minimum 4 weeks (planned) Tongue scraping for treating halitosis (2006) · Cochrane | No randomized controlled trials comparing mechanical tongue cleaning with mouthwashes were identified; the review notes "the somewhat unexpected lack of randomized controlled trials comparing the effectiveness of… | 0 studies | No studies |
Lingualised teeth (maxillary anatomic + mandibular non-anatomic; lingualised occlusion scheme) vs Zero-degree teeth (non-anatomic, cuspless) Patient perceived comfort · Edentulous adult patients requiring complete dentures Interventions for replacing missing teeth: denture chewing surface designs in edentulous people (2005) · Cochrane | no estimate extracted | NR | No studies |
Lingualised teeth (maxillary anatomic + mandibular non-anatomic; lingualised occlusion scheme) vs Zero-degree teeth (non-anatomic, cuspless) Patient perceived masticatory/chewing efficiency · Edentulous adult patients requiring complete dentures Interventions for replacing missing teeth: denture chewing surface designs in edentulous people (2005) · Cochrane | no estimate extracted | NR | No studies |
Lingualised teeth (maxillary anatomic + mandibular non-anatomic; lingualised occlusion scheme) vs Zero-degree teeth (non-anatomic, cuspless) Patient perceived masticatory/chewing function · Edentulous adult patients requiring complete dentures Interventions for replacing missing teeth: denture chewing surface designs in edentulous people (2005) · Cochrane | no estimate extracted | NR | No studies |
Direct resin composite veneer vs Indirect resin composite veneer Adverse reactions · Patients with permanent anterior teeth with intrinsic staining suitable for laminate veneer restorations Direct versus indirect veneer restorations for intrinsic dental stains (2004) · Cochrane | Planned outcome; no adverse-reaction data were reported by the included trial. | 0 studies | No studies |
Fluoride mouthrinse, gel or varnish combined with fluoride toothpaste (any combined regimen) vs Fluoride toothpaste alone Enamel fluorosis (adverse effect) · Children or adolescents aged 16 years or less Combinations of topical fluoride (toothpastes, mouthrinses, gels, varnishes) versus single topical fluoride… (2004) · Cochrane | Fluorosis data have not been reported in any of the trials. | 0 studies | No studies |
Direct resin composite veneer vs Indirect resin composite veneer Pain following treatment · Patients with permanent anterior teeth with intrinsic staining suitable for laminate veneer restorations Direct versus indirect veneer restorations for intrinsic dental stains (2004) · Cochrane | Planned outcome; pain following treatment was not reported by the included trial (earlier trial publications reported treatment times, not pain). | 0 studies | No studies |
Direct resin composite veneer vs Indirect resin composite veneer Cost of treatment · Patients with permanent anterior teeth with intrinsic staining suitable for laminate veneer restorations Direct versus indirect veneer restorations for intrinsic dental stains (2004) · Cochrane | Planned outcome; cost of treatment was not reported by the included trial. | 0 studies | No studies |
Ozone applied to the carious lesion (10 or 40 seconds), with a fluoride reductant and oral hygiene/preventive advice vs No ozone, with a fluoride reductant and oral hygiene/preventive advice (as in the intervention group) Further conventional dental treatment (filling and drilling) (binary yes/no) · People of any age with caries (including demineralisation in non-cavitated carious lesions); the caries may affect any… Ozone therapy for the treatment of dental caries (2004) · Cochrane | Data were not provided by any study on the number of lesions requiring restorations to 6 months or later; no data on any further conventional treatment or other dental interventions. | NR | No studies |
Ozone applied to the carious lesion (10 or 40 seconds), with a fluoride reductant and oral hygiene/preventive advice vs No ozone, with a fluoride reductant and oral hygiene/preventive advice (as in the intervention group) Cost · People of any age with caries (including demineralisation in non-cavitated carious lesions); the caries may affect any… Ozone therapy for the treatment of dental caries (2004) · Cochrane | No data were provided in any of the included trials on costs. | NR | No studies |
Ozone applied to the carious lesion (10 or 40 seconds), with a fluoride reductant and oral hygiene/preventive advice vs No ozone, with a fluoride reductant and oral hygiene/preventive advice (as in the intervention group) Pain (assessed by the patient) · People of any age with caries (including demineralisation in non-cavitated carious lesions); the caries may affect any… Ozone therapy for the treatment of dental caries (2004) · Cochrane | No data were provided in any of the included trials on pain. | NR | No studies |
Ozone applied to the carious lesion (10 or 40 seconds), with a fluoride reductant and oral hygiene/preventive advice vs No ozone, with a fluoride reductant and oral hygiene/preventive advice (as in the intervention group) Time to intervention · People of any age with caries (including demineralisation in non-cavitated carious lesions); the caries may affect any… Ozone therapy for the treatment of dental caries (2004) · Cochrane | No data were provided in any of the included trials on time to intervention. | NR | No studies |