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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. Words match anywhere in the field.
175 questions in 21 reviews · cluster CL0065
current versionsNo studies 0 · 0%Ungraded 170 · 97.1%Very low 2 · 1.1%Low 1 · 0.6%Moderate 0 · 0%High 2 · 1.1%
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.
Intervention categories, outcome domains and clusters are a proposed key pending human validation. Clear all filters
| Question | Effect | Evidence | Status / GRADE |
|---|---|---|---|
E-cigarette use (ENDS / vaping) vs Non-smokers Dental caries experience (DMFT/DMFS index) · Humans who use e-cigarettes (adolescents to adults) assessed for dental caries · Cross-sectional to 6 months The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d 0.93 [-1.11, 2.98] | 3 studies | Ungraded |
Lower unemployment rate vs Higher unemployment rate (low <=5% / medium >5-10% / high >10%) Caries experience (mean DMFT) · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), Low unemployment (<=5%) Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | MEAN 1.23 | NR | Ungraded |
Higher per-capita expenditure on dental health care vs Lower per-capita expenditure on dental health care (USD bands: $0-50 / $51-100 / >$100) Caries experience (mean DMFT) · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), $0-50 per capita Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | MEAN 3.06 [2.32, 3.79] | 14 studies | Ungraded |
Epilepsy (as exposure/condition) vs Healthy participants without epilepsy (control group) dmft (primary teeth) · Children and adolescents with epilepsy · Children/adolescents Evaluating the DMFT and dmft indices in people with epilepsy: A systematic review and meta-analysis. (2025) | SMD 0.132 [-0.220, 0.484] | NR | Ungraded |
All dental health care expenditure strata vs No comparator (single-group pooled mean) DMFT caries experience · 12-year-old children in European countries · 2011-2022, Overall Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | Mean DMFT 2.10 [1.61, 2.59] | 32 studies | Ungraded |
Western/Northern Europe (UN M49 region) vs Eastern/Southern Europe (UN M49 geographical categorization) Caries experience (mean DMFT) · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), North Europe Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | MEAN 1.34 [0.62, 2.06] | 8 studies | Ungraded |
All GNI strata vs No comparator (single-group pooled mean) DMFT caries experience · 12-year-old children in European countries · 2011-2022, Overall Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | Mean DMFT 2.10 [1.63, 2.57] | 34 studies | Ungraded |
All M49 regions vs No comparator (single-group pooled mean) DMFT caries experience · 12-year-old children in European countries · 2011-2022, Overall Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | Mean DMFT 2.10 [1.63, 2.57] | 34 studies | Ungraded |
Western/Northern Europe (UN M49 region) vs Eastern/Southern Europe (UN M49 geographical categorization) Caries experience (mean DMFT) · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), East Europe Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | MEAN 2.76 [2.44, 3.08] | 9 studies | Ungraded |
Very high Human Development Index (HDI >=0.800) vs High Human Development Index (HDI 0.700-0.799) Caries experience (mean DMFT) · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), High HDI (0.700-0.799) Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | MEAN 3.41 | NR | Ungraded |
Lower unemployment rate vs Higher unemployment rate (low <=5% / medium >5-10% / high >10%) Caries experience (mean DMFT) · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), Medium unemployment (>5-10%) Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | MEAN 2.08 | NR | Ungraded |
Epilepsy (as exposure/condition) vs Healthy participants without epilepsy (control group) DMFT (permanent teeth) · Children and adolescents with epilepsy · Children/adolescents Evaluating the DMFT and dmft indices in people with epilepsy: A systematic review and meta-analysis. (2025) | SMD 0.334 [-0.140, 0.827] | NR | Ungraded |
Epilepsy (as exposure/condition) vs Healthy participants without epilepsy (control group) DMFT (decayed, missing, filled permanent teeth) · People with epilepsy (children, adolescents, and adults) Evaluating the DMFT and dmft indices in people with epilepsy: A systematic review and meta-analysis. (2025) | SMD 0.403 [0.057, 0.749] | 7 studies | High |
All European countries pooled (overall) vs None (overall pooled prevalence) Caries experience (mean DMFT) · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), Overall Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | MEAN 2.10 [1.63, 2.57] | 34 studies · 493360 participants | Ungraded |
Epilepsy (as exposure/condition) vs Healthy participants without epilepsy (control group) DMFT (permanent teeth) · Adults with epilepsy · Adults Evaluating the DMFT and dmft indices in people with epilepsy: A systematic review and meta-analysis. (2025) | SMD 0.548 [0.223, 0.873] | NR | Ungraded |
Western/Northern Europe (UN M49 region) vs Eastern/Southern Europe (UN M49 geographical categorization) Caries experience (mean DMFT) · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), West Europe Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | MEAN 0.88 [0.54, 1.22] | 5 studies | Ungraded |
Lower unemployment rate vs Higher unemployment rate (low <=5% / medium >5-10% / high >10%) Odds of higher caries (DMFT) category · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), Unemployment rate (ordinal logistic regression, adjusted) Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | OR 0.99 [0.44, 2.23] | NR | Ungraded |
Epilepsy (as exposure/condition) vs Healthy participants without epilepsy (control group) dmft (decayed, missing, filled primary teeth) · People with epilepsy (children, adolescents, and adults) Evaluating the DMFT and dmft indices in people with epilepsy: A systematic review and meta-analysis. (2025) | SMD 0.132 [-0.22, 0.484] | 5 studies | High |
Western/Northern Europe (UN M49 region) vs Eastern/Southern Europe (UN M49 geographical categorization) Odds of higher caries (DMFT) category · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), Geographical location (ordinal logistic regression, adjusted) Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | OR 0.57 [0.24, 1.35] | NR | Ungraded |
Western/Northern Europe (UN M49 region) vs Eastern/Southern Europe (UN M49 geographical categorization) Caries experience (mean DMFT) · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), South Europe Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | MEAN 2.61 [1.60, 3.62] | 12 studies | Ungraded |
Electronic cigarette use vs Non-smokers DMFT/DMFS score · People who use electronic cigarettes · Overall The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Cohen's d 0.93 [-1.11, 2.98] | 3 studies | Ungraded |
Higher per-capita expenditure on dental health care vs Lower per-capita expenditure on dental health care (USD bands: $0-50 / $51-100 / >$100) Caries experience (mean DMFT) · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), >$100 per capita Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | MEAN 0.96 [0.64, 1.28] | 12 studies | Ungraded |
Very high Human Development Index (HDI >=0.800) vs High Human Development Index (HDI 0.700-0.799) Odds of higher caries (DMFT) category · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), Human Development Index (ordinal logistic regression, adjusted) Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | OR 1.82 [0.32, 10.47] | NR | Ungraded |
Higher per-capita expenditure on dental health care vs Lower per-capita expenditure on dental health care (USD bands: $0-50 / $51-100 / >$100) Caries experience (mean DMFT) · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), $51-100 per capita Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | MEAN 2.14 [1.40, 2.89] | 6 studies | Ungraded |
Epilepsy (exposure) vs Healthy participants dmft index (primary teeth) · Children or adolescents with epilepsy · Children or adolescents Evaluating the DMFT and dmft indices in people with epilepsy: A systematic review and meta-analysis. (2025) | SMD 0.132 [-0.220, 0.484] | NR | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Mean dmft (caries severity) · Children aged 0-5 years in North Africa · Overall Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | MEAN 2.95 [1.86, 4.67] | 13 studies | Ungraded |
Very high Human Development Index (HDI >=0.800) vs High Human Development Index (HDI 0.700-0.799) Caries experience (mean DMFT) · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), Very high HDI (>=0.800) Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | MEAN 1.73 | NR | Ungraded |
Anorexia nervosa (as exposure; diagnosed by DSM-III/III-R/IV/V) vs Healthy individuals without anorexia nervosa (age- and sex-matched controls) Caries experience (DMFT index) · Patients with anorexia nervosa aged >=12 years (mean age ~18.4; entirely female in reported data), general… The influence of anorexia nervosa on oral health and related parameters potentially relevant to orthodontic… (2025) | MD 2.00 [0.87, 3.13] | 4 studies · 406 participants | Low |
Lower unemployment rate vs Higher unemployment rate (low <=5% / medium >5-10% / high >10%) Caries experience (mean DMFT) · 12-year-old children across European countries (national/regional epidemiological surveys, 2011-2022) · Cross-sectional (survey data 2011-2022), High unemployment (>10%) Caries status in 12-year-old children, geographical location and socioeconomic conditions across European… (2025) | MEAN 2.38 | NR | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries experience (mean dmft) · Children younger than 71 months (under 6 years) · Gini index: low inequality A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 1.62 | NR | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries experience (mean dmft) · Children younger than 71 months (under 6 years) · Region: Middle East A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 5.53 [3.94, 7.13] | 6 studies | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC) prevalence (%, dmft>0) · Children younger than 71 months (under 6 years) · Region: Europe A systematic review and meta-analysis on early-childhood-caries global data. (2024) | Prevalence 36 [25, 47] | 13 studies | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries experience (mean dmft) · Children younger than 71 months (under 6 years) · Region: Africa A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 3.47 [1.37, 5.56] | 3 studies | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries experience (mean dmft) · Children younger than 71 months (under 6 years) · GNI >$40000 A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 3.34 [1.79, 4.88] | 13 studies | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries experience (mean dmft) · Children younger than 71 months (under 6 years) · GNI <$5000 A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 4.64 [3.38, 5.91] | 19 studies | Ungraded |
Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population Dental caries experience (mean DMFT) · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | Mean DMFT (usually reported at population level) ranged from 0.26 to 16.6 across studies; the Missing component was typically highest and the Filled component lowest, reflecting limited access to dental care. | 12 studies | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries experience (mean dmft) · Children younger than 71 months (under 6 years) · Region: Asia-Oceania A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 3.87 [2.84, 4.91] | 30 studies | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC) prevalence (%, dmft>0) · Children younger than 71 months (under 6 years) · Life expectancy: 71-75 years A systematic review and meta-analysis on early-childhood-caries global data. (2024) | Prevalence 62 | NR | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC) prevalence (%, dmft>0) · Children younger than 71 months (under 6 years) · GNI >$40000 A systematic review and meta-analysis on early-childhood-caries global data. (2024) | Prevalence 47 [32, 62] | 14 studies | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries experience (mean dmft) · Children younger than 71 months (under 6 years) · Region: North America A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 3.89 [1.62, 6.16] | 7 studies | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries experience (mean dmft) · Children younger than 71 months (under 6 years) · GNI $10000-$19999 A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 4.04 [2.39, 5.68] | 9 studies | Ungraded |
Oral cancer patients (cases) vs Healthy controls DMFT index in OC cases vs controls · Adults in case-control studies (oral cancer patients vs healthy controls) · Not specified, DMFT (decayed, missing, filled teeth) Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies. (2024) | SMD 0.65 [0.12, 1.18] | 2 studies | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries experience (mean dmft) · Children younger than 71 months (under 6 years) · Life expectancy: 71-75 years A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 5.18 | NR | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC) prevalence (%, dmft>0) · Children younger than 71 months (under 6 years) · Gini index: no inequality A systematic review and meta-analysis on early-childhood-caries global data. (2024) | Prevalence 62 | NR | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC) prevalence (%, dmft>0) · Children younger than 71 months (under 6 years) · Region: Africa A systematic review and meta-analysis on early-childhood-caries global data. (2024) | Prevalence 42 [32, 53] | 3 studies | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC) prevalence (%, dmft>0) · Children younger than 71 months (under 6 years) · Region: Asia-Oceania A systematic review and meta-analysis on early-childhood-caries global data. (2024) | Prevalence 52 [45, 60] | 33 studies | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries experience (mean dmft) · Children younger than 71 months (under 6 years) · GNI $5000-$9999 A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 4.28 [2.58, 5.97] | 10 studies | Ungraded |
Institutionalization (living in an orphanage/institution) vs Parented children living with their families Permanent-teeth caries experience (DMF/DMFT, mean score) · Institutionalized orphan children (roughly 3 to 18 years) · Overall (pooled) Caries in orphan children: prevalence and determinants-a systematic review and meta-analysis. (2024) | MD 0.09 [-0.36, 0.55] | 7 studies · 2676 participants | Very low |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries experience (mean dmft) · Children younger than 71 months (under 6 years) · Gini index: no inequalities A systematic review and meta-analysis on early-childhood-caries global data. (2024) | MEAN 3.95 | NR | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC) prevalence (%, dmft>0) · Children younger than 71 months (under 6 years) · Overall (all regions) A systematic review and meta-analysis on early-childhood-caries global data. (2024) | Prevalence 49 [44, 55] | 67 studies | Ungraded |