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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. Every word you type has to appear somewhere in the question, and the closest matches are ranked first.

Limit to evidence status or GRADE (optional)

75,239 questions in 5,342 reviews

current versions
No 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.

QuestionEffectEvidenceStatus / GRADE
Summary of findings table ‐ Sodium modelling vs slow dialysis
Adverse events · haemodialysis patients
Interventions for preventing haemodialysis dysequilibrium syndrome (2024) · Cochrane
RR 1.33 [0.15, 11.64]1 study · 15 participantsVery low
Summary of findings table ‐ Sodium modelling vs slow dialysis
Duration of hospital stay ‐ not reported · haemodialysis patients
Interventions for preventing haemodialysis dysequilibrium syndrome (2024) · Cochrane
no estimate extractedNRNo studies
Summary of findings table ‐ High sodium dialysate vs standard sodium dialysate
Dialysis dysequilibrium syndrome · haemodialysis patients
Interventions for preventing haemodialysis dysequilibrium syndrome (2024) · Cochrane
RR 0.07 [0, 1.12]1 study · 22 participantsVery low
Summary of findings table ‐ High sodium dialysate vs standard sodium dialysate
Severe dialysis dysequilibrium syndrome · haemodialysis patients
Interventions for preventing haemodialysis dysequilibrium syndrome (2024) · Cochrane
RR 0.47 [0.02, 10.32]1 study · 22 participantsVery low
Summary of findings table ‐ High sodium dialysate vs standard sodium dialysate
Death · haemodialysis patients
Interventions for preventing haemodialysis dysequilibrium syndrome (2024) · Cochrane
no estimate extracted1 study · 22 participantsVery low
Summary of findings table ‐ High sodium dialysate vs standard sodium dialysate
Adverse events · haemodialysis patients
Interventions for preventing haemodialysis dysequilibrium syndrome (2024) · Cochrane
RR 0.29 [0.08, 1.02]1 study · 22 participantsVery low
Sodium‐glucose co‐transporter protein 2 (SGLT2) inhibitors vs placebo
All‐cause death median · people with CKD and diabetes
Asked by 2 reviewsSodium‐glucose co‐transporter protein 2 (SGLT2) inhibitors for people with chronic kidney disease and diabetes (2024) · Cochrane
RR 0.86 [0.81, 0.92]20 studies · 44397 participantsHigh
Sodium‐glucose co‐transporter protein 2 (SGLT2) inhibitors vs placebo
3P‐MACE median · people with CKD and diabetes
Sodium‐glucose co‐transporter protein 2 (SGLT2) inhibitors for people with chronic kidney disease and diabetes (2024) · Cochrane
RR 0.89 [0.81, 0.98]7 studies · 38320 participantsModerate
Sodium‐glucose co‐transporter protein 2 (SGLT2) inhibitors vs placebo
4P‐MACE median · people with CKD and diabetes
Sodium‐glucose co‐transporter protein 2 (SGLT2) inhibitors for people with chronic kidney disease and diabetes (2024) · Cochrane
RR 0.82 [0.7, 0.96]4 studies · 23539 participantsModerate
Sodium‐glucose co‐transporter protein 2 (SGLT2) inhibitors vs placebo
Kidney composite outcome median · people with CKD and diabetes
Sodium‐glucose co‐transporter protein 2 (SGLT2) inhibitors for people with chronic kidney disease and diabetes (2024) · Cochrane
RR 0.68 [0.59, 0.78]7 studies · 36380 participantsHigh
Sodium‐glucose co‐transporter protein 2 (SGLT2) inhibitors vs placebo
Kidney failure median · people with CKD and diabetes
Sodium‐glucose co‐transporter protein 2 (SGLT2) inhibitors for people with chronic kidney disease and diabetes (2024) · Cochrane
RR 0.7 [0.62, 0.79]6 studies · 11232 participantsHigh
Sodium‐glucose co‐transporter protein 2 (SGLT2) inhibitors vs placebo
Hypoglycaemia requiring third‐party assistance median · people with CKD and diabetes
Sodium‐glucose co‐transporter protein 2 (SGLT2) inhibitors for people with chronic kidney disease and diabetes (2024) · Cochrane
RR 0.75 [0.65, 0.88]14 studies · 26478 participantsHigh
Sodium‐glucose co‐transporter protein 2 (SGLT2) inhibitors vs placebo
Diabetic ketoacidosis median · people with CKD and diabetes
Sodium‐glucose co‐transporter protein 2 (SGLT2) inhibitors for people with chronic kidney disease and diabetes (2024) · Cochrane
RR 2.05 [1.34, 3.14]13 studies · 38710 participantsModerate
wMel‐Wolbachia infected Aedes aegypti deployments vs no deployments
Virologically confirmed dengue case incidence (any severity, any phenotype) · children and adults at risk of dengue infection
Wolbachia ‐carrying Aedes mosquitoes for preventing dengue infection (2024) · Cochrane
no estimate extractedNRNo studies
wMel‐Wolbachia infected Aedes aegypti deployments vs no deployments
Prevalence of DENV infection (any severity, any phenotype)a · children and adults at risk of dengue infection
Wolbachia ‐carrying Aedes mosquitoes for preventing dengue infection (2024) · Cochrane
OR 0.23 [0.15, 0.35]6306 participantsModerate
wMel‐Wolbachia infected Aedes aegypti deployments vs no deployments
Prevalence of dengue RNA in the mosquito population · children and adults at risk of dengue infection
Wolbachia ‐carrying Aedes mosquitoes for preventing dengue infection (2024) · Cochrane
no estimate extractedNRNo studies
wMel‐Wolbachia infected Aedes aegypti deployments vs no deployments
Mosquito density (for population suppression strategy) · children and adults at risk of dengue infection
Wolbachia ‐carrying Aedes mosquitoes for preventing dengue infection (2024) · Cochrane
no estimate extractedNRNo studies
wMel‐Wolbachia infected Aedes aegypti deployments vs no deployments
Prevalence of Wolbachia‐carrying mosquitoes (for population replacement strategy) · children and adults at risk of dengue infection
Wolbachia ‐carrying Aedes mosquitoes for preventing dengue infection (2024) · Cochrane
no estimate extractedNRNo studies
wMel‐Wolbachia infected Aedes aegypti deployments vs no deployments
Adverse events potentially related to Wolbachia‐carrying Aedes deployments · children and adults at risk of dengue infection
Wolbachia ‐carrying Aedes mosquitoes for preventing dengue infection (2024) · Cochrane
no estimate extractedNRNo studies
Intervention NR
Difference between effect estimates from RCTs and observational studies [for RCTs vs OBSs] · systematic reviews and overviews of systematic reviews
Healthcare outcomes assessed with observational study designs compared with those assessed in randomized… (2024) · Cochrane
no estimate extractedNRLow
Highest BMI category (overweight/obese) vs Lowest BMI category (normal weight/underweight)
Dental caries / early childhood caries (ECC) · Children (approx. 4-18 years) · Dental examinations of children; 15 countries across Europe, Asia, the Americas and Oceania, Adjustment for sex: yes
Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024)
OR 1.30 [0.99, 1.71]10 studiesUngraded
Teledentistry (index test): dental caries diagnosis from photographs taken with DSLR or smartphone cameras; store-and-forward vs Visual/clinical dental examination (reference standard)
Sensitivity · Children and adults with primary or permanent dentition undergoing dental caries assessment · Cross-sectional diagnostic accuracy (index test vs reference standard, in-vivo), In-vivo: dental clinics/hospitals, schools, and a juvenile detention facility (11 countries), Overall (studies reporting sensitivity; narrative synthesis)
Teledentistry accuracy for caries diagnosis: a systematic review of in-vivo studies using extra-oral… (2024)
Sensitivity Overall 48% to 98.3% across 13 studies; sensitivity is lesion-stage dependent: Kohara reported <40% for initial/moderate caries (75-100% for extensive) and early enamel lesions were less sensitive13 studiesUngraded
Fixed orthodontic treatment with fixed (multibracket) appliances (exposure) vs None (single-group prevalence/incidence estimate)
Association between orthodontic treatment duration and ICLs incidence · Patients undergoing fixed orthodontic treatment with fixed (multibracket) appliances, followed for development of new… · During or after fixed orthodontic treatment, International (16 countries; studies published 2005-2022); orthodontic clinical settings, By orthodontic treatment duration (subgroup meta-analysis; positive association, P<.01)
Distribution of initial caries lesions in relation to fixed orthodontic therapy. A systematic review and… (2024)
Incidence of new ICLs positively associated with orthodontic treatment duration (meta-regression, P<.01); effect size/slope not available (Fig. 6b image not provided)NRUngraded
Probiotics (any strain, dose, or presentation), minimum intake duration 0.2 months vs No treatment or placebo (control)
Number of dental caries (carious pieces) · Children and/or adolescents (<18 years) without background systemic disease · follow-up: mean 26 months, Healthy children and/or adolescents (<18 years) without systemic disease; RCTs from multiple countries (India, Thailand, Spain, Australia, New Zealand, Sweden, Poland, Colombia, Saudi Arabia); mostly school/community and clinic settings, Overall (all presentations pooled)
Efficacy of Probiotic Consumption on Oral Outcomes in Children and/or Adolescents: A Meta-Analysis. (2024)
MD -0.24 [-0.72, 0.23]6 studies · 1049 participantsLow
Consumption of xylitol chewing gum by women (mothers) vs Consumption of CHX/xylitol gum by women, or CHX varnish applied to women's dentition
defs index score · For interventions, pregnant women and mothers of infants in the first year of life; for outcomes, children up to 6…
Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane
MD -0.28 [-0.83, 0.27]1 study · 96 participantsVery low
Silver diamine fluoride (SDF; 38% in most trials, 30% in three) vs Placebo (inactive control)
Caries arrestment at the individual (patient) level · Children and adults with active dental caries (aged 1-50; mostly preschool/school children with primary dentition) · 3 weeks to 12 months, Children/adults with dental caries; multiple countries; community/clinic care setting not clearly specified, SDF vs placebo
The role of silver diamine fluoride as dental caries preventive and arresting agent: a systematic review and… (2024)
OR 18.10 [3.89, 84.15]2 studies · 102 participantsUngraded
Silver diamine fluoride (SDF) vs Glass ionomer cement (GIC) plus fluoride varnish
Caries arrest · Children and adults (with or without carious lesions) · 6 months, Primary dentition (coronal)
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
OR 1.89 [0.61, 5.87]1 study · 69 participantsVery low
Silver diamine fluoride (SDF) vs Fluoride varnish
Secondary prevention of caries · Children and adults (with or without carious lesions) · 30 months, Primary dentition
Topical silver diamine fluoride (SDF) for preventing and managing dental caries in children and adults (2024) · Cochrane
MD 0.04 [-0.30, 0.38]1 study · 309 participantsVery low
Breastfeeding for <6 months vs Breastfeeding for ≥6 months
Dental caries (early childhood caries) · Preschool children (<6 years) · Preschool children in high- and middle-income countries; caries assessed in clinical or field/community settings, Cohort studies
Association of Breastfeeding and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024)
RR 0.97 [0.88, 1.06]6 studies · 4850 participantsUngraded
Xylitol (low-intensity sweetener/sugar alcohol) in food products (chewing gum, milk, candy, or tablets) vs No treatment (no gum / no intervention)
Change in Mutans streptococci (MS) count in dental plaque · Generally healthy individuals across all age groups (infants to elderly) · Post-consumption endpoint (trial durations 2 wk to 6 mo), All age groups, generally healthy; multiple countries; sugar substitutes delivered as chewing gum, milk, candy, or tablets, Xylitol gum vs no treatment (5 studies, mixed ages)
Clinical Effects of Sugar Substitutes on Cariogenic Bacteria: A Systematic Review and Meta-Analysis. (2024)
SMD -0.73 [-1.09, -0.37]5 studies · 308 participantsUngraded
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence)
Poor (inadequate) oral hygiene (prevalence) · Children (<18 years) with intellectual and developmental disabilities (IDD) in India · India (Karnataka, Tamil Nadu, Rajasthan, Maharashtra); schools/institutions and community, Overall
Oral health status of children with intellectual and developmental disabilities in India: a systematic… (2024)
Prevalence 38 [21, 59]5 studies · 1333 participantsUngraded
TT+TC genotypes vs CC genotype
Dental caries · Children (<18 years) with vs without dental caries · Dominant model (TT+TC vs CC), Children under 18 years; case-control and cross-sectional studies (China, Czech Republic, Turkey, Brazil, India)
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 0.75 [0.54, 1.05]5 studies · 1606 participantsUngraded
Minimally invasive caries removal (MIT): selective removal to soft dentin, self-limiting chemomechanical removal, or partial/incomplete caries removal vs Conventional caries removal (CT): selective removal to firm dentin, stepwise excavation, or complete caries removal
Restoration/treatment success rate · Patients with deep carious lesions in permanent (mainly posterior) teeth · 1 to 5 years (follow-up varied by study)
Comparative Meta-Analysis of Minimally Invasive and Conventional Approaches for Caries Removal in Permanent… (2024)
Mean success-rate percentage (unweighted study-level mean, 7 studies) MIT 83.6% vs CT 75.4% (Mann-Whitney U = 0.2, p > 0.05; not statistically significant)7 studies · 1305 participantsUngraded
Occlusal splint vs Another occlusal splint with a different mechanism of action
Range of mandibular motion · People with temporomandibular disorders (TMD) · Short term (12 weeks), Mixed TMD
Occlusal interventions for managing temporomandibular disorders (2024) · Cochrane
MD 0.63 [-3.16, 4.42]1 study · 40 participantsUngraded
TT+CC (homozygous) genotypes vs TC (heterozygous) genotype
Dental caries · Children (<18 years) with vs without dental caries · Over-dominant model (TT+CC vs TC), Children under 18 years; case-control and cross-sectional studies (China, Czech Republic, Turkey, Brazil, India), Primary dentition
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 1.49 [0.97, 2.28]NRUngraded
TT+TC genotypes vs CC genotype
Dental caries · Children (<18 years) with vs without dental caries · Dominant model (TT+TC vs CC), Children under 18 years; case-control and cross-sectional studies (China, Czech Republic, Turkey, Brazil, India), Asian ethnicity
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 0.69 [0.44, 1.07]NRUngraded
Orthodontic adhesives containing bioactive glass (BAG) particles/nanoparticles (including fluoride- or Ga-doped BAG) vs Conventional/control orthodontic adhesive (e.g., Transbond XT) or negative control
Ion release (fluoride, calcium, phosphate) · Human enamel specimens around orthodontic brackets (in vitro) · 14 days [31] and 20 days [27,28] (per Discussion); ion-release durations for [23,24] not reported, In vitro (laboratory), Overall
Remineralization and anti-demineralization effect of orthodontic adhesives on enamel surrounding orthodontic… (2024)
Ion release from BAG-containing adhesives was assessed in 5 studies [23, 24, 27, 28, 31]; a significant increase of phosphate ion release with gallium-doped bioactive glass nanoparticles up to 14 days was reported…5 studiesUngraded
Oral health education/promotion (oral hygiene advice plus diet and feeding practice advice) combined with clinical treatment for mother's dentition (basic restorative and preventive; 1 trial included CHX varnish application) vs Standard care
Caries presence in primary teeth · For interventions, pregnant women and mothers of infants in the first year of life; for outcomes, children up to 6… · Children assessed at 18-24 months
Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane
RR 0.44 [0.05, 3.95]2 studies · 324 participantsVery low
nCaF2 primer vs Control Transbond primer
Streptococcus mutans count · Patients undergoing fixed orthodontic treatment · 1, 3, and 6 months after bonding, Fixed orthodontic treatment
Can Orthodontic Adhesive Systems Inhibit the Formation and Development of White Spot Lesions During Fixed… (2024)
Statistically significant difference in bacterial count between the two primers only at T1 (p-value = 0.000).1 study · 31 participantsUngraded
Facemask vs Untreated control (no treatment)
Overjet · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · 3-year follow-up
Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane
MD 2.50 [1.21, 3.79]1 study · 63 participantsModerate
Facemask with rapid maxillary expansion (RME) vs Facemask only
Overjet · Children and adolescents (aged 16 years or younger) with prominent lower front teeth (Class III malocclusion) · End of treatment
Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children (2024) · Cochrane
MD 1.86 [0.39, 3.33]1 study · 31 participantsLow
Antioxidants (lycopene, curcumin, Oxitard) vs Placebo or no active treatment
Participant satisfaction · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF)
Interventions for managing oral submucous fibrosis (2024) · Cochrane
The trials did not measure participant satisfaction.0 studiesNo studies
Grape seed extract (GSE) and its proanthocyanidin fractions vs Untreated or vehicle control (some studies vs positive antimicrobial controls, e.g. chlorhexidine/fluoride)
Biofilm formation (reduction) · Streptococcus mutans (in vitro cultures and biofilms) · in vitro (laboratory)
Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024)
GSE reduced biofilm formation: 89% (polymeric PAC) vs 79% (dealcoholized wine) (Daglia), inhibition at 4 mg/mL (Zhao), decreased microcolonies with 2000 ug/mL GSE + fluorinol (Furiga), reduction within 30 min…5 studiesUngraded
Superelastic NiTi arch wire vs Thermoelastic NiTi arch wire
Alignment rate · People receiving orthodontic treatment with fixed appliances (upper and/or lower full arch) · 4 to 16 weeks
Initial arch wires used in orthodontic treatment with fixed appliances (2024) · Cochrane
MD -0.28 [-0.62, 0.06]5 studies · 183 participantsLow
Advice about a healthy diet (including breastfeeding promotion and sugar avoidance) and feeding practices (e.g. relating to bottle-feeding and sleep) for infants and young children vs Standard care
dmft index score (decayed, missing, filled primary teeth; range 0-20) · For interventions, pregnant women, mothers or other caregivers of infants in the first year of life; for outcomes,… · Children assessed at 4 yrs
Interventions with pregnant women, new mothers and other primary caregivers for preventing early childhood… (2024) · Cochrane
MD -0.90 [-1.85, 0.05]1 study · 340 participantsVery low
TT+CC (homozygous) genotypes vs TC (heterozygous) genotype
Dental caries · Children (<18 years) with vs without dental caries · Over-dominant model (TT+CC vs TC), Children under 18 years; case-control and cross-sectional studies (China, Czech Republic, Turkey, Brazil, India), Asian ethnicity
Association of vitamin D receptor gene polymorphisms with caries risk in children: a systematic review and… (2024)
OR 1.38 [1.02, 1.87]NRUngraded
Cranberry extract or cranberry flavonoid fractions vs No extract or vehicle control; other antimicrobial agents
Biofilm formation · Streptococcus mutans cultures and biofilms · In vitro laboratory studies
Effect of flavonoids from grape seed and cranberry extracts on the microbiological activity of Streptococcus… (2024)
no estimate extracted10 studiesUngraded
Intralesional betamethasone vs Placebo
Maximal mouth opening (interincisal distance) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF)
Interventions for managing oral submucous fibrosis (2024) · Cochrane
Goel 2015 (3-arm: intralesional betamethasone vs lycopene vs placebo, 90 per arm): appeared to show increased interincisal distance in both intervention groups vs placebo, but only between-group differences with no…1 study · 180 participantsUngraded
Intralesional triamcinolone vs Intralesional triamcinolone plus salvianolic acid B
Burning sensation (VAS 0-100) · People of any age with a confirmed diagnosis, by clinical examination and biopsy, of oral submucous fibrosis (OSF) · Less than 3 months
Interventions for managing oral submucous fibrosis (2024) · Cochrane
MD -1.00 [-10.37, 8.37]1 study · 28 participantsVery low
Gene sequencing (GS) applied to diagnose/manage oral conditions (predominantly 16S rRNA next-generation sequencing of the oral microbiome; also genome-wide/whole-genome sequencing) vs Negligible ('abysmal') effect of gene sequencing; no separate comparator arm (within-sample event contrast in the forest plots)
Noticeable impact of gene sequencing on diagnosing/managing oral conditions · Human patients (any age) with oral-cavity related disorders (e.g. dental caries, periodontitis, gingivitis,… · Various countries; clinical trials of the oral microbiome/genetics, Overall
Gene sequencing applications to combat oral-cavity related disorders: a systematic review with meta-analysis. (2024)
OR 0.30 [0.26, 0.33]8 studies · 2211 participantsUngraded