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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.
56 questions in 15 reviews · cluster CL0063
current versionsNo studies 0 · 0%Ungraded 52 · 92.9%Very low 3 · 5.4%Low 0 · 0%Moderate 1 · 1.8%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.
Intervention categories, outcome domains and clusters are a proposed key pending human validation. Clear all filters
| Question | Effect | Evidence | Status / GRADE |
|---|---|---|---|
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC), prevalence · Children aged 0-5 years in North Africa · Country: Tunisia Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 38 [24, 51] | 4 studies | Ungraded |
Higher parental education (tertiary) vs Lower parental education (reference) Early childhood caries (ECC) · Children aged 0-5 years in North Africa · Paternal tertiary education [Kabil] Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 0.381 [0.16, 0.91] | 1 study | Ungraded |
Caries in mother's mouth vs No maternal caries Early childhood caries (ECC) · Children aged 0-5 years in North Africa Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 20.44 [8.37, 49.92] | 1 study | Ungraded |
Iron deficiency anemia (IDA) vs Children without anemia (non-anemic) Dental caries (presence) · Children and adolescents (0-18 years; most included reviews focused on <6 years) Association Between Iron Deficiency Anemia and Dental Caries in Children: A Systematic Umbrella Meta-Analysis. (2025) | OR 3.64 [2.45, 5.40] | 3 studies | Moderate |
Spoon sharing with household members vs No spoon sharing Early childhood caries (ECC) · Children aged 0-5 years in North Africa Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 8.79 [2.92, 26.51] | 1 study | Ungraded |
Higher parental education (tertiary) vs Lower parental education (reference) Early childhood caries (ECC) · Children aged 0-5 years in North Africa · Maternal tertiary education [Kabil] Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 0.083 [0.03, 0.21] | 1 study | Ungraded |
Older child age (months) vs Younger age (reference) Early childhood caries (ECC) · Children aged 0-5 years in North Africa · 48-59 months Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 2.602 [1.122, 2.302] | 1 study | Ungraded |
Timing of first dental visit vs Reference visit timing Early childhood caries (ECC) · Children aged 0-5 years in North Africa · Early visit Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 0.042 [0.013, 0.136] | 1 study | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC), prevalence · Children aged 0-5 years in North Africa · Sample size <500 Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 48 [39, 58] | 9 studies | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC), prevalence · Children aged 0-5 years in North Africa · Country: Sudan Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 63 [52, 74] | 3 studies | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC), prevalence · Children aged 0-5 years in North Africa · Sample size >500 Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 65 [55, 75] | 9 studies | Ungraded |
E-cigarette use (ENDS / vaping) vs Non-smokers Untreated dental caries and caries risk · Humans who use e-cigarettes (adolescents to adults) assessed for dental caries · Cross-sectional The effects of electronic smoking on dental caries and proinflammatory markers: a systematic review and… (2025) | Narrative synthesis (not meta-analyzed). E-cigarette users had more untreated caries and higher caries risk than non-smokers in individual studies: Vemulapalli 2021 untreated-caries OR 2.04 (non-smokers as reference);… | 3 studies | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC), prevalence · Children aged 0-5 years in North Africa · Publication-bias adjusted (trim-and-fill) Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 62 [58, 81] | NR | Ungraded |
Nocturnal (night) feeding vs No nocturnal feeding Early childhood caries (ECC) · Children aged 0-5 years in North Africa Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 2.417 [1.340, 4.358] | 1 study | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC), prevalence · Children aged 0-5 years in North Africa · Country: Egypt Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 62 [53, 70] | 10 studies | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC), prevalence · Children aged 0-5 years in North Africa · Overall (all included studies) Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 57 [50, 64] | 18 studies · 11319 participants | Ungraded |
Feeding on demand vs Scheduled feeding Early childhood caries (ECC) · Children aged 0-5 years in North Africa Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 9.66 [4.26, 21.93] | 1 study | Ungraded |
Male sex vs Female sex Early childhood caries (ECC) · Children aged 0-5 years in North Africa Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 2.911 [1.42, 5.99] | 1 study | Ungraded |
Prior history of dental visit vs No prior dental visit Early childhood caries (ECC) · Children aged 0-5 years in North Africa Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 2.444 [1.108, 2.072] | 1 study | Ungraded |
Higher parental education (tertiary) vs Lower parental education (reference) Early childhood caries (ECC) · Children aged 0-5 years in North Africa · Parents' education level [Chouchene] Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 0.797 [0.171, 0.650] | 1 study | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC), prevalence · Children aged 0-5 years in North Africa · Sampling: convenience Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 60 | 4 studies | Ungraded |
Timing of first dental visit vs Reference visit timing Early childhood caries (ECC) · Children aged 0-5 years in North Africa · Delayed/late visit Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 0.248 [0.072, 0.852] | 1 study | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC), prevalence · Children aged 0-5 years in North Africa · Sampling: stratified/multistage cluster Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 50 [40, 61] | 9 studies | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Early childhood caries (ECC), prevalence · Children aged 0-5 years in North Africa · Sampling: simple random Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | Prevalence 67 | 5 studies | Ungraded |
Older child age (months) vs Younger age (reference) Early childhood caries (ECC) · Children aged 0-5 years in North Africa · 60-71 months Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 2.845 [1.128, 2.072] | 1 study | Ungraded |
Having siblings vs No siblings Early childhood caries (ECC) · Children aged 0-5 years in North Africa · 1 sibling Prevalence and risk factors for early childhood caries in North Africa: a systematic review and meta-analysis. (2025) | OR 3.32 [1.15, 9.54] | 1 study | Ungraded |
Acidic bacillary pH on teeth vs Non-acidic bacillary pH Dental caries · Primary school children in Ethiopia Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | OR 2.42 [1.494, 3.335] | NR | Ungraded |
Poor habit of tooth cleaning vs Good tooth-cleaning habit Dental caries · Primary school children in Ethiopia Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | OR 3.90 [2.761, 5.045] | NR | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Dental caries, prevalence · Primary school children in Ethiopia · Sampling technique: systematic random sampling Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | Prevalence 30 [15, 44] | 2 studies · 554 participants | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Dental caries, prevalence · Primary school children in Ethiopia · Sampling technique: multi-stage random sampling Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | Prevalence 21 [19, 23] | 1 study · 1736 participants | Ungraded |
Slum residence vs Non-slum urban residence Dental caries (odds), slum vs non-slum residence · Adult residents of slums and non-slum urban settings of LMICs · Cross-sectional, Slum vs non-slum urban (Osuh 2022, Nigeria) Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries… (2024) | OR 1.21 [0.94, 1.56] | 1 study · 1357 participants | Ungraded |
Male sex vs Female sex Dental caries risk · Institutionalized orphan children · Overall (pooled) Caries in orphan children: prevalence and determinants-a systematic review and meta-analysis. (2024) | RR 1.02 [0.96, 1.08] | 5 studies · 2750 participants | Very low |
Serum 25(OH)D < 50 nmol/l vs Serum 25(OH)D ≥ 75 nmol/l Early childhood caries (ECC) · Preschool children ≤6 years The Association Between Vitamin D and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | OR 2.00 [1.76, 2.28] | 6 studies · 4807 participants | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Dental caries, prevalence · Primary school children in Ethiopia · Sampling technique: simple random sampling Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | Prevalence 42 [35, 49] | 4 studies · 1421 participants | Ungraded |
Grade level 1-4 (first cycle) vs Grade level 5 or above Dental caries · Primary school children in Ethiopia Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | OR 2.46 [1.523, 3.397] | NR | Ungraded |
High intake of sweets vs Lower/less intake of sweets Dental caries · Primary school children in Ethiopia Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | OR 2.71 [1.968, 3.451] | 5 studies | Ungraded |
Serum 25(OH)D 50–75 nmol/l vs Serum 25(OH)D ≥ 75 nmol/l Early childhood caries (ECC) · Preschool children ≤6 years The Association Between Vitamin D and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | OR 1.42 [1.26, 1.60] | 6 studies · 5746 participants | Ungraded |
Primary teeth / primary dentition (younger children) vs Permanent teeth / permanent dentition (older children) Dental caries risk · Institutionalized orphan children · Overall (pooled) Caries in orphan children: prevalence and determinants-a systematic review and meta-analysis. (2024) | RR 1.31 [0.91, 1.89] | 5 studies · 1892 participants | Very low |
Genome-wide common variants (aggregate additive; LD score regression) vs Not applicable (variance-component estimate) Dental caries - SNP-based heritability · Japanese adults (present-study cohort) · Lifelong (germline genotype), LDSC heritability (present study) Genome-wide association meta-analysis identifies two novel loci associated with dental caries. (2024) | h2 (observed-scale SNP heritability) 0.0258 | 1 study · 45525 participants | Ungraded |
Higher waist circumference vs Lower waist circumference Dental caries in children · Children (approx. 4-18 years) Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… (2024) | OR 1.08 [0.90, 1.30] | 2 studies | Ungraded |
Serum 25(OH)D < 50 nmol/l vs Serum 25(OH)D 50–75 nmol/l Early childhood caries (ECC) · Preschool children ≤6 years The Association Between Vitamin D and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | OR 1.47 [1.30, 1.66] | 6 studies · 5265 participants | Ungraded |
Serum 25(OH)D 50–75 nmol/l vs Serum 25(OH)D ≥ 75 nmol/l Early childhood caries (ECC) · Preschool children ≤6 years, North America · North America The Association Between Vitamin D and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | OR 2.09 [1.55, 2.82] | 3 studies · 750 participants | Ungraded |
Serum 25(OH)D 50–75 nmol/l vs Serum 25(OH)D ≥ 75 nmol/l Early childhood caries (ECC) · Preschool children ≤6 years, Asia and Europe · Asia and Europe The Association Between Vitamin D and Early Childhood Caries: A Systematic Review and Meta-Analysis. (2024) | OR 1.32 [1.17, 1.50] | 3 studies · 4996 participants | Ungraded |
History of toothache vs No history of toothache Dental caries · Primary school children in Ethiopia Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | OR 2.99 [2.679, 3.314] | NR | Ungraded |
Not applicable (single-group prevalence) vs Not applicable (single-group prevalence) Dental caries, prevalence · Primary school children in Ethiopia · Overall (all included studies) Prevalence of dental caries and associated factors among primary school children in Ethiopia: systematic… (2024) | Prevalence 35 [27, 43] | 7 studies · 3711 participants | Ungraded |
Mixed breast- and bottle-feeding vs Bottle-feeding only Dental caries (early childhood caries) · Healthy children under 6 years in South Africa Maternal and infant risk factors and risk indicators associated with early childhood caries in South Africa:… (2022) | OR 1.04 [0.76, 1.41] | 2 studies · 863 participants | Ungraded |
Food and nonalcoholic beverage marketing (exposure) vs No, less, or less powerful food marketing Dental caries · Children and adolescents aged 0-19 years · Nonrandomized studies Association of Food and Nonalcoholic Beverage Marketing With Children and Adolescents' Eating Behaviors and… (2022) | Vote counting: 1 of 2 studies (50%; 95% CI, 9%-90.5%) showed an association of public health harm; 1 moderate-quality study found a clear association with caries and 1 high-quality study found no association. | 2 studies | Very low |
Parental tertiary education vs Parental high school (secondary) education Dental caries (early childhood caries) · Healthy children under 6 years in South Africa Maternal and infant risk factors and risk indicators associated with early childhood caries in South Africa:… (2022) | OR 1.77 [1.22, 2.57] | 2 studies · 505 participants | Ungraded |
Bottle-feeding only vs Breastfeeding only Dental caries (early childhood caries) · Healthy children under 6 years in South Africa Maternal and infant risk factors and risk indicators associated with early childhood caries in South Africa:… (2022) | OR 1.30 [0.84, 2.02] | 2 studies · 911 participants | Ungraded |
High snack consumption vs Low snack consumption Severe early childhood caries · Children aged 5-6 years in Ajman schools · Overall Oral Health of Children and Adolescents in the United Arab Emirates: A Systematic Review of the Past Decade. (2021) | OR 1.80 [1.26, 2.58] | 1 study · 1036 participants | Ungraded |