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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.
75,239 questions in 5,342 reviews
current versionsNo studies 15,213 · 20.2%Ungraded 10,323 · 13.7%Very low 17,528 · 23.3%Low 17,951 · 23.9%Moderate 11,190 · 14.9%High 3,034 · 4%
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 |
|---|---|---|---|
AFI vs SDVP: summary of findings table Caesarean delivery for fetal distress · pregnant women to prevent adverse pregnancy outcome Amniotic fluid index versus single deepest vertical pocket as a screening test for preventing adverse… (2008) · Cochrane | RR 1.46 [1.08, 1.96] | 5 studies · 3226 participants | Moderate |
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 Change in HbA1c from baseline to endpoint % ( · patients with type 2 diabetes mellitus Dipeptidyl peptidase‐4 (DPP‐4) inhibitors for type 2 diabetes mellitus (2008) · Cochrane | no estimate extracted | 14 studies · 6308 participants | High |
Intervention NR Change in HbA1c from baseline to endpoint ‐ Vildagliptin versus another single hypoglycaemic agent % ( · patients with type 2 diabetes mellitus Dipeptidyl peptidase‐4 (DPP‐4) inhibitors for type 2 diabetes mellitus (2008) · Cochrane | no estimate extracted | 3 studies · 1764 participants | High |
Intervention NR Change in HbA1c from baseline to endpoint ‐ Vildagliptin versus placebo % ( · patients with type 2 diabetes mellitus Dipeptidyl peptidase‐4 (DPP‐4) inhibitors for type 2 diabetes mellitus (2008) · Cochrane | no estimate extracted | 6 studies · 1139 participants | High |
Intervention NR Change in body weight from baseline to endpoint ‐ Vildagliptin versus placebo kg ( · patients with type 2 diabetes mellitus Dipeptidyl peptidase‐4 (DPP‐4) inhibitors for type 2 diabetes mellitus (2008) · Cochrane | no estimate extracted | 3 studies · 484 participants | High |
Intervention NR Adverse events ‐ All‐cause infections ( · patients with type 2 diabetes mellitus Dipeptidyl peptidase‐4 (DPP‐4) inhibitors for type 2 diabetes mellitus (2008) · Cochrane | RR 1.04 [0.87, 1.24] | 10 studies · 3573 participants | High |
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 Change in HbA1c from baseline to endpoint % ( · type 2 diabetes mellitus Dipeptidyl peptidase‐4 (DPP‐4) inhibitors for type 2 diabetes mellitus (2008) · Cochrane | no estimate extracted | 11 studies · 6907 participants | High |
Intervention NR Change in HbA1c from baseline to endpoint ‐ Sitagliptin versus another single hypoglycaemic agent % ( · type 2 diabetes mellitus Dipeptidyl peptidase‐4 (DPP‐4) inhibitors for type 2 diabetes mellitus (2008) · Cochrane | no estimate extracted | 2 studies · 592 participants | High |
Intervention NR Change in HbA1c from baseline to endpoint [%] ‐ Sitagliptin versus placebo % ( · type 2 diabetes mellitus Dipeptidyl peptidase‐4 (DPP‐4) inhibitors for type 2 diabetes mellitus (2008) · Cochrane | no estimate extracted | 3 studies · 1103 participants | High |
Intervention NR Change in body weight from baseline to endpoint ‐ Sitagliptin versus placebo kg ( · type 2 diabetes mellitus Dipeptidyl peptidase‐4 (DPP‐4) inhibitors for type 2 diabetes mellitus (2008) · Cochrane | no estimate extracted | 3 studies · 1109 participants | High |
Intervention NR Adverse events ‐ All‐cause infections ( · type 2 diabetes mellitus Dipeptidyl peptidase‐4 (DPP‐4) inhibitors for type 2 diabetes mellitus (2008) · Cochrane | RR 1.29 [1.09, 1.52] | 8 studies · 3589 participants | High |
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 |
Zinc chloride + sodium chlorite mouthrinse (TriOral) vs Control mouthrinse (containing neither zinc chloride nor sodium chlorite) Organoleptic assessment (indirect surrogate salivary organoleptic score) · Adults over 18 years with a clinical or self-assessed diagnosis of halitosis, without significant comorbidity (e.g.… · 4 weeks Mouthrinses for the treatment of halitosis (2008) · Cochrane | Codipilly 2004: only indirect surrogate salivary organoleptic scores were reported (not organoleptic breath scores); no accurate deductions could be made from the reported values. | 1 study | Ungraded |
Systemic oral acyclovir vs Placebo or no treatment Fever (duration; time to return to normal temperature) · Children and young adults under 25 years with primary herpetic gingivostomatitis (with or without herpes labialis) Acyclovir for treating primary herpetic gingivostomatitis (2008) · Cochrane | Amir 1997b: fever disappeared significantly earlier with acyclovir (median 1 day) than placebo (median 3 days); difference in median (95% CI): From 72: 1 (0.0 to 2.0); From 61: 2 (0.8 to 3.2); reported as median, not… | 2 studies | Ungraded |
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 |
Zinc chloride without sodium chlorite mouthrinse (Breath Rx containing cetylpyridinium chloride) vs Control mouthrinse (containing neither zinc chloride nor sodium chlorite) Halimeter-assessed volatile sulphur compounds (VSC) · Adults over 18 years with a clinical or self-assessed diagnosis of halitosis, without significant comorbidity (e.g.… · 4 weeks Mouthrinses for the treatment of halitosis (2008) · Cochrane | Codipilly 2004: reported VSC reduction from baseline for zinc chloride minus sodium chlorite (Breath Rx containing cetylpyridinium chloride): 38% (P < 0.05) at 2 weeks, versus a control containing neither zinc chloride… | 1 study | Ungraded |
Systemic oral acyclovir vs Placebo or no treatment Patient or parental satisfaction (tolerance and acceptability of drug) · Children and young adults under 25 years with primary herpetic gingivostomatitis (with or without herpes labialis) Acyclovir for treating primary herpetic gingivostomatitis (2008) · Cochrane | Amir 1997b: no data available. Ducoulombier 1988: tolerance and acceptability of the drug was described as satisfactory, but it was unclear how this was assessed by the trialists. | 1 study | Ungraded |
Minimal incision palatopharyngoplasty (MIPP) vs MIPP with additional individualised velopharyngeal surgery (pharyngeal flap or sphincter pharyngoplasty) Adverse effect: failure of muscle fusion in the region of the cleft after surgery · 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 | There were no reports of failure of muscle fusion after surgery. | 1 study · 72 participants | Ungraded |
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 |
Systemic oral acyclovir vs Placebo or no treatment Adverse effects · Children and young adults under 25 years with primary herpetic gingivostomatitis (with or without herpes labialis) Acyclovir for treating primary herpetic gingivostomatitis (2008) · Cochrane | Amir 1997b: two children in each group (2 vs 2) had mild gastrointestinal symptoms that resolved spontaneously after 24 to 48 hours without a change in study treatment. Ducoulombier 1988: no significant adverse effects… | 2 studies | Ungraded |
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 |
Minimal incision palatopharyngoplasty (MIPP) vs MIPP with additional individualised velopharyngeal surgery (pharyngeal flap or sphincter pharyngoplasty) Adverse effect: obstructive sleep apnoea or airway compromise · 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 investigators stated that none of the participants reported obstructive sleep apnoea after the interventions. | 1 study · 72 participants | Ungraded |
Minimal incision palatopharyngoplasty (MIPP) vs MIPP with additional individualised velopharyngeal surgery (pharyngeal flap or sphincter pharyngoplasty) Perceptual speech assessment: residual post-operative velopharyngeal insufficiency · Children or adolescents aged 3 years or older with velopharyngeal insufficiency (VPI) associated with non-syndromic… · 3 months post-operatively Interventions for the management of submucous cleft palate (2008) · Cochrane | Five (14%) of the participants in group 1 (MIPP) and four (11%) in group 2 had residual post-operative velopharyngeal insufficiency, P > 0.05. The report provided no details on post-operative speech assessment other… | 1 study · 72 participants | Ungraded |
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 |
Systemic oral acyclovir vs Placebo or no treatment Pain/discomfort (time to resolution of pain) · Children and young adults under 25 years with primary herpetic gingivostomatitis (with or without herpes labialis) Acyclovir for treating primary herpetic gingivostomatitis (2008) · Cochrane | Amir 1997b: no data available. Ducoulombier 1988: time to resolution of pain, acyclovir (1 day=1, 2 days=1, 3 days=3, 4 days=3, 5 days=1, persistent=0) vs placebo (1 day=0, 2 days=0, 3 days=1, 4 days=2, 5 days=4,… | 1 study · 18 participants | Ungraded |
Occlusal adjustment as an adjunct to surgical periodontal therapy vs Surgical periodontal therapy alone (no occlusal adjustment) Probing (pocket) depth change (difference in mean reduction, mm) · Adults (aged 18 years or older) with a clinical diagnosis of (chronic) periodontitis · 2 years Occlusal interventions for periodontitis in adults (2008) · Cochrane | MD 0.01 [-0.20, 0.22] | 1 study · 50 participants | Ungraded |
Occlusal adjustment as an adjunct to non-surgical periodontal therapy vs Non-surgical periodontal therapy alone (no occlusal adjustment) Clinical attachment level change (mean gain, mm) · Adults (aged 18 years or older) with a clinical diagnosis of (chronic) periodontitis · 2 years Occlusal interventions for periodontitis in adults (2008) · Cochrane | MD 0.38 [0.04, 0.72] | 1 study · 50 participants | Ungraded |
Conditioning and sealing with an adhesive resin (smear-removing bonding system) vs Conventional calcium hydroxide lining Maintenance of pulp vitality (freedom from pulpal breakdown) up to 36 months · Healthy adults with asymptomatic posterior permanent teeth with deep caries and a vital (non-exposed) pulp requiring… · 36 months Pulp management for caries in adults: maintaining pulp vitality (2007) · Cochrane | Whitworth 2005: 602 teeth randomised; 39 emergency recalls over the 36 months after restoration, with pulp breakdown associated with 16 teeth. The authors concluded that "dentists should be confident that pulps will be… | 1 study · 602 participants | Ungraded |
Occlusal splint vs Palatal splint Total sleep time (min) · 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 | MD -8.60 [-96.17, 78.97] | 1 study | Ungraded |
Antifungal drugs partially absorbed from GI tract (miconazole, clotrimazole) vs Placebo or no treatment Systemic fungal infection · Patients with cancer receiving chemotherapy or radiotherapy or both Interventions for preventing oral candidiasis for patients with cancer receiving treatment (2007) · Cochrane | RR 2.27 [0.23, 22.56] | 1 study · 32 participants | Ungraded |
Antifungal drugs not absorbed from GI tract vs Placebo or no treatment Oral candidiasis (present) · Patients with cancer receiving chemotherapy or radiotherapy or both Interventions for preventing oral candidiasis for patients with cancer receiving treatment (2007) · Cochrane | RR 0.69 [0.47, 1.01] | 8 studies · 382 participants | Ungraded |
Occlusal splint vs Palatal splint Sleep efficiency (%) · 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 | MD -2.40 [-8.36, 3.56] | 1 study | Ungraded |
Amphotericin B vs Placebo or no treatment Oral candidiasis (present) · Patients with cancer receiving chemotherapy or radiotherapy or both Interventions for preventing oral candidiasis for patients with cancer receiving treatment (2007) · Cochrane | RR 0.46 [0.18, 1.23] | 2 studies · 48 participants | Ungraded |
Itraconazole vs Fluconazole Empirical antifungal treatment · Patients with cancer receiving chemotherapy or radiotherapy or both Interventions for preventing oral candidiasis for patients with cancer receiving treatment (2007) · Cochrane | RR 0.5 [0.05, 5.43] | 1 study · 202 participants | Ungraded |
Occlusal splint vs Mandibular advancement device Pain during the night (adverse effect) · 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 | Occlusal splint versus mandibular advancement device (Landry 2006): pain during the night occurred with the MAD max and MAD min configurations (8/13). | 1 study | Ungraded |
Psychological intervention based on a specified psychological model/theory (to increase adherence to oral hygiene instructions) vs No (active) intervention (usual/standard dental care or no-treatment control) Observed flossing skill · Adults (aged 18 or over) diagnosed with periodontal disease (gingivitis or periodontitis) · 4 months Psychological interventions to improve adherence to oral hygiene instructions in adults with periodontal… (2007) · Cochrane | Little 1997 observed and rated participants on flossing skill; Analysis of Covariance found a significant difference favouring the intervention group. | 1 study · 107 participants | Ungraded |
Antifungal drugs absorbed from GI tract (fluconazole, ketoconazole, itraconazole) vs Placebo or no treatment Systemic fungal infection · Patients with cancer receiving chemotherapy or radiotherapy or both Interventions for preventing oral candidiasis for patients with cancer receiving treatment (2007) · Cochrane | RR 0.65 [0.37, 1.14] | 6 studies · 1041 participants | Ungraded |
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 |
Glycerrhetinic acid/antibiotic mixture vs Calcium hydroxide Clinical success (survival free of symptoms) at 24 months · Adults with asymptomatic teeth with vital carious pulp exposures · 24 months Pulp management for caries in adults: maintaining pulp vitality (2007) · Cochrane | Shovelton 1971 (Analysis 1.1): 275 teeth followed for 2 years (235 at 6 months, 160 at 12 months, 85 analysed at 24 months). Success rates 50% to 80%. Ledermix and calcium hydroxide had the highest success rates,… | 1 study · 275 participants | Ungraded |
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 |
Psychological intervention based on a specified psychological model/theory (to increase adherence to oral hygiene instructions) vs No (active) intervention (usual/standard dental care or no-treatment control) Plaque score · Adults (aged 18 or over) diagnosed with periodontal disease (gingivitis or periodontitis) Psychological interventions to improve adherence to oral hygiene instructions in adults with periodontal… (2007) · Cochrane | The impact of psychological interventions on clinical markers was assessed in three studies (Little 1997; Stewart 1991; Weinstein 1996). All three found that psychological interventions resulted in improved plaque… | 3 studies | Ungraded |
Antifungal drugs absorbed from GI tract (fluconazole, ketoconazole, itraconazole) vs Placebo or no treatment Empirical antifungal treatment · Patients with cancer receiving chemotherapy or radiotherapy or both Interventions for preventing oral candidiasis for patients with cancer receiving treatment (2007) · Cochrane | RR 0.85 [0.73, 0.99] | 2 studies · 465 participants | Ungraded |
Psychological intervention based on a specified psychological model/theory (to increase adherence to oral hygiene instructions) vs No (active) intervention (usual/standard dental care or no-treatment control) Self-efficacy beliefs (flossing) · Adults (aged 18 or over) diagnosed with periodontal disease (gingivitis or periodontitis) Psychological interventions to improve adherence to oral hygiene instructions in adults with periodontal… (2007) · Cochrane | Stewart 1996: the psychological intervention group demonstrated significantly higher change in self efficacy scores for flossing at post-intervention compared to the other two groups (control and educational). Flossing… | 1 study · 117 participants | Ungraded |
Occlusal splint vs Mandibular advancement device Oral dryness (adverse effect) · 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 | Occlusal splint versus mandibular advancement device (Landry 2006): oral dryness occurred with the MAD min configuration (7/13). | 1 study | Ungraded |
Ledermix (corticosteroid/antibiotic pulp-capping cement) vs Calcium hydroxide Clinical success (survival free of symptoms) at 24 months · Adults with asymptomatic teeth with vital carious pulp exposures · 24 months Pulp management for caries in adults: maintaining pulp vitality (2007) · Cochrane | Shovelton 1971 (Analysis 1.1): 275 teeth followed for 2 years (235 at 6 months, 160 at 12 months, 85 analysed at 24 months). Success rates 50% to 80%. Ledermix and calcium hydroxide had the highest success rates,… | 1 study · 275 participants | Ungraded |