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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.
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 |
|---|---|---|---|
Booster vs placebo/no booster Serious adverse events Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
CVnCoV – CureVac AG vs placebo Confirmed SARS‐CoV‐2 infection Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
ChAdOx1 – AstraZeneca + University of Oxford vs placebo Severe or critical COVID‐19 Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
SII‐ChAdOx1 – Serum Institute of India/AstraZeneca + University of Oxford vs ChAdOx1 – University of Oxford Confirmed SARS‐CoV‐2 infection Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
SII‐ChAdOx1 – Serum Institute of India/AstraZeneca + University of Oxford vs ChAdOx1 – University of Oxford Confirmed symptomatic COVID‐19 Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
SII‐ChAdOx1 – Serum Institute of India/AstraZeneca + University of Oxford vs ChAdOx1 – University of Oxford Severe or critical COVID‐19 Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
SII‐ChAdOx1 – Serum Institute of India/AstraZeneca + University of Oxford vs ChAdOx1 – University of Oxford All‐cause mortality Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
AD26.COV2.S – Janssen Pharmaceutical Companies vs placebo Confirmed SARS‐CoV‐2 infection Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
Gam‐COVID‐VAC – Sputnik V vs placebo Confirmed SARS‐CoV‐2 infection Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
BNT162b2 – Pfizer/BioNTech + Fosun Pharma vs placebo Systemic reactogenicity events Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
Gam‐COVID‐VAC – Sputnik V vs placebo Systemic reactogenicity events Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
Gam‐COVID‐VAC – Sputnik V vs placebo Any adverse event Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
Gam‐COVID‐VAC – Sputnik V vs placebo Local reactogenicity events Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
CoronaVac – Sinovac vs placebo Confirmed SARS‐CoV‐2 infection Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
WIBP‐CorV – Sinopharm‐Wuhan vs placebo Severe or critical COVID‐19 Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
WIBP‐CorV – Sinopharm‐Wuhan vs placebo All‐cause mortality Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
BBIBP‐CorV – Sinopharm‐Beijing vs placebo Severe or critical COVID‐19 Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
BBIBP‐CorV – Sinopharm‐Beijing vs placebo All‐cause mortality Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
BNT162b2 – Pfizer/BioNTech + Fosun Pharma vs placebo Local reactogenicity events Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
NVX‐CoV2373 – Novavax vs placebo Confirmed SARS‐CoV‐2 infection Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
FINLAY‐FR‐2 – Instituto Finlay de Vacunas vs placebo Confirmed SARS‐CoV‐2 infection Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
FINLAY‐FR‐2 – Instituto Finlay de Vacunas vs placebo Severe or critical COVID‐19 Efficacy and safety of COVID‐19 vaccines (2022) · Cochrane | no estimate extracted | NR | No studies |
Intervention NR Wait‐list compared with no‐treatment · patients with mental health disorders Control interventions in randomised trials among people with mental health disorders (2022) · Cochrane | no estimate extracted | NR | No studies |
Intervention NR Serious adverse events for all placebos · patients with mental health disorders Control interventions in randomised trials among people with mental health disorders (2022) · Cochrane | no estimate extracted | NR | No studies |
Intervention NR Non‐serious adverse events for all placebos · patients with mental health disorders Control interventions in randomised trials among people with mental health disorders (2022) · Cochrane | no estimate extracted | NR | No studies |
Flowable resin composite vs Fluoride-releasing resin-based sealant Development of >=1 new carious lesion (caries incidence) · Children who were regular dental attenders with caries-free first or second primary molars (public health service… Sealants for preventing dental caries in primary teeth (2022) · Cochrane | No studies reported this outcome. | 0 studies | No studies |
New restorative materials with bio-active molecules (bio-active materials, BM) vs Any restorative material or technique Not applicable (no eligible studies) · Children with carious primary teeth (no pulp therapy) Clinical effectiveness of restorative materials for the restoration of carious primary teeth without pulp… (2022) | The search retrieved no randomized controlled trials on the clinical effectiveness of new bio-active restorative materials for carious primary teeth. | 0 studies | No studies |
Responsive / non-responsive complementary feeding (RCF/NRCF) vs Other models of complementary feeding Choking · Healthy, term-born, normal-birth-weight infants aged 4-24 months (breastfed and/or formula-fed) in Western… · Infancy, Outpatient care in Western industrialized (European/Anglo-Saxon) countries Complementary Feeding Caregivers' Practices and Growth, Risk of Overweight/Obesity, and Other… (2022) | No SRs or studies relevant to the risk of choking were found that included NRCF or RCF approaches other than those specifically defined as BLW or BLISS. | 0 studies | No studies |
Autopolymerised sealant vs Light polymerised sealant Progression of non-cavitated enamel caries · Children with sound primary molars, aged 2-4 years (municipal dental clinics or hospital paediatric clinics, Denmark) Sealants for preventing dental caries in primary teeth (2022) · Cochrane | No studies reported on this outcome. | 0 studies | No studies |
Professional oral care vs Usual oral care Change in systemic antibiotic use · Residents of nursing homes and other long-term care facilities Oral care measures for preventing nursing home‐acquired pneumonia (2022) · Cochrane | No studies measured change in systemic antibiotic use. | 0 studies | No studies |
Antibiotic prophylaxis before dental procedure vs No antibiotic prophylaxis or placebo Adverse effects of antibiotics · Adults or children at increased risk of bacterial endocarditis (pre-existing cardiac condition) undergoing an invasive… Antibiotic prophylaxis for preventing bacterial endocarditis following dental procedures (2022) · Cochrane | Adverse effects of antibiotics | No data reported | 248 (1 study) | - | - | 0 studies | No studies |
Combined antiretroviral therapy (cART) vs Monotherapy or dual antiretroviral therapy Oral hairy leukoplakia prevalence · Children and adolescents (<18 years) living with HIV (CLWH) · Hospitals and AIDS outpatient centres in India, Brazil, and several Asian countries Impact of Antiretroviral Therapy on Oral Health among Children Living with HIV: A Systematic Review and… (2022) | No eligible studies compared oral hairy leukoplakia between CLWH on different ART medications. | 0 studies | No studies |
Traditional screening (referral card given if the inspecting dentist judges the child needs to see a dentist) vs No screening Adverse events · School children (aged 4 to 15 years), primary and secondary schools in the UK and India School dental screening programmes for oral health (2022) · Cochrane | Adverse events: Not reported (Summary of findings 1). | 0 studies | No studies |
Periodontal treatment (subgingival instrumentation, with or without antimicrobials/surgery) vs No active intervention/usual care Diabetic complications · People with diabetes mellitus (type 1 or type 2, mostly type 2) and periodontitis, at least 16 years of age · 3-4 months Treatment of periodontitis for glycaemic control in people with diabetes mellitus (2022) · Cochrane | Included studies did not report data on diabetic complications (some reported medication changes only) | 0 studies | No studies |
Food and nonalcoholic beverage marketing (exposure) vs No, less, or less powerful food marketing Diet-related noncommunicable diseases · Children and adolescents aged 0-19 years · Predominantly high-income countries Association of Food and Nonalcoholic Beverage Marketing With Children and Adolescents' Eating Behaviors and… (2022) | No studies were found with relevant data on diet-related noncommunicable diseases or validated surrogate indicators. | 0 studies | No studies |
Antibiotic prophylaxis before dental procedure vs No antibiotic prophylaxis or placebo Cost implications of antibiotic provision · Adults or children at increased risk of bacterial endocarditis (pre-existing cardiac condition) undergoing an invasive… Antibiotic prophylaxis for preventing bacterial endocarditis following dental procedures (2022) · Cochrane | The study did not provide any data on mortality, adverse events requiring hospitalisation, adverse effects of antibiotics or cost implications of treatment. | 0 studies | No studies |
Any preprocedural mouth rinse vs Placebo, no rinsing or control Cost · Dental patients undergoing aerosol-generating procedures (AGPs) Preprocedural mouth rinses for preventing transmission of infectious diseases through aerosols in dental… (2022) · Cochrane | No included study reported cost. | 0 studies | No studies |
Fluoride-containing dental care products (toothpaste) vs Dietary/other fluoride sources Contribution of dental care products to total fluoride exposure · Pregnant and lactating women Fluoride Intake Through Dental Care Products: A Systematic Review. (2022) | no estimate extracted | 0 studies | No studies |
Full-mouth scaling (FMS): scaling/root planing (subgingival instrumentation) of all quadrants within 24 hours, without antiseptic vs Full-mouth disinfection (FMD): scaling/root planing (subgingival instrumentation) of all quadrants within 24 hours plus adjunctive antiseptic (chlorhexidine) treatments (rinsing, pocket irrigation, tongue/tonsil brushing) Tooth loss · Adults with a clinical diagnosis of (chronic) periodontitis (1999 classification); studies of aggressive… Full‐mouth treatment modalities (within 24 hours) for periodontitis in adults (2022) · Cochrane | Tooth loss: None of the studies comparing FMS vs FMD reported tooth loss. | 0 studies | No studies |
Responsive complementary feeding (RCF) / other caregivers' feeding practices vs Other models of complementary feeding (traditional/non-responsive CF) Dental caries (later in life) · Healthy, term-born, normal-birth-weight infants aged 4-24 months (breastfed and/or formula-fed) in Western… · Later in life, Outpatient care in Western industrialized (European/Anglo-Saxon) countries Complementary Feeding Caregivers' Practices and Growth, Risk of Overweight/Obesity, and Other… (2022) | No studies on the influence of caregivers' feeding practices during complementary feeding on dental caries later in life were identified. | 0 studies | No studies |
Traditional screening (referral card given if the inspecting dentist judges the child needs to see a dentist) vs No screening Cost effectiveness · School children (aged 4 to 15 years), primary and secondary schools in the UK and India School dental screening programmes for oral health (2022) · Cochrane | As none of the studies reported cost-effectiveness, we could not assess the cost-benefit aspect of school dental screening. | 0 studies | No studies |
Periodontal treatment (subgingival instrumentation, with or without antimicrobials/surgery) vs No active intervention/usual care Cost implications · People with diabetes mellitus (type 1 or type 2, mostly type 2) and periodontitis, at least 16 years of age · 3-4 months Treatment of periodontitis for glycaemic control in people with diabetes mellitus (2022) · Cochrane | Included studies did not report cost data. A brief economic commentary drew on four external economic evaluations (Smits 2020, Nasseh 2017, Choi 2020, Soloweij-Wedderburn 2017) suggesting potential cost… | 0 studies | No studies |
Cognitive behavioural therapy (CBT) vs Usual care, waiting list or no treatment (control) Additional physical symptoms · People aged 12 years and over with painful TMD lasting 3 months or longer Psychological therapies for temporomandibular disorders (TMDs) (2022) · Cochrane | This outcome was not measured for this comparison. | NR | No studies |
Glass ionomer-based sealant vs No sealant Progression of non-cavitated enamel caries · Children with caries-free primary first molars (with or without caries on other teeth), aged 1-5 years (paediatric… Sealants for preventing dental caries in primary teeth (2022) · Cochrane | No studies reported this outcome. | 0 studies | No studies |
Fluoride-releasing resin-based sealant vs No sealant (no treatment) Progression of non-cavitated enamel caries · Children with caries-free or non-cavitated carious lesion primary molars, aged 3-7 years (paediatric department,… Sealants for preventing dental caries in primary teeth (2022) · Cochrane | No studies reported this outcome. | 0 studies | No studies |
Full-mouth scaling (FMS): scaling/root planing (subgingival instrumentation) of all quadrants within 24 hours, without antiseptic vs Quadrant scaling and root planing (control): SRP of each quadrant in separate sessions at least one week apart Tooth loss · Adults with a clinical diagnosis of (chronic) periodontitis (1999 classification); studies of aggressive… Full‐mouth treatment modalities (within 24 hours) for periodontitis in adults (2022) · Cochrane | Tooth loss: None of the studies comparing FMS vs control reported tooth loss. | 0 studies | No studies |
Oral cytology (e.g. OralCDx brush biopsy, CytID) vs Reference standard: examination and clinical evaluation by a physician/clinician with specialist knowledge or training (long-term follow-up accepted for those screened negative) Outcome NR · Apparently healthy adults not reporting symptoms of OPMD or OSCC, attending an organised screening or surveillance… Clinical assessment for the detection of oral cavity cancer and potentially malignant disorders in… (2021) · Cochrane | Oral cytology (e.g. brush biopsy) was added to the list of eligible index tests in this update; no eligible studies evaluated it (evidence gap). | 0 studies | No studies |
Double primary (canine and first molar) tooth extraction vs Single primary (canine) tooth extraction Root resorption of the impacted canine or adjacent incisors and first premolars · Young people aged 9 to 14 years diagnosed with one or both palatally displaced permanent maxillary canines (PDC) Interventions for promoting the eruption of palatally displaced permanent canine teeth, without the need for… (2021) · Cochrane | The studies did not report adverse events. | 0 studies | No studies |
ARP with alloplast plus barrier membrane vs ARP with alloplast without membrane Aesthetic outcomes of future prosthodontic rehabilitation · Adults aged 18 years or older, in good general health (including well-controlled systemic disease), requiring… · 9 months Interventions for replacing missing teeth: alveolar ridge preservation techniques for dental implant site… (2021) · Cochrane | Outcome not reported | 0 studies | No studies |
COE with blood/salivary (biomarker) analysis vs Reference standard: examination and clinical evaluation by a physician/clinician with specialist knowledge or training (long-term follow-up accepted for those screened negative) Outcome NR · Apparently healthy adults not reporting symptoms of OPMD or OSCC, attending an organised screening or surveillance… Clinical assessment for the detection of oral cavity cancer and potentially malignant disorders in… (2021) · Cochrane | There were no eligible studies evaluating blood or salivary sample analysis (which tests for the presence of biomarkers for OPMD and OSCC). | 0 studies | No studies |