What do systematic reviews say?

Vitamin D (higher dose) + micronutrient(s) vs vitamin D (lower dose) + micronutrient(s)

The review found no eligible studies for this question.

• Effects of oral vitamin D supplementation on linear growth and other health outcomes among children under five years… 2020 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Summary of findings: Higher bladder volume vs lower bladder volume

The review found no eligible studies for this question.

• Interventions to reduce acute and late adverse gastrointestinal effects of pelvic radiotherapy for primary pelvic… 2018 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Summary of findings: Higher bladder volume vs lower bladder volume

Summary of findings: Higher bladder volume showed no clear difference in acute and late GI toxicity (grade 2+) compared with lower bladder volume (low certainty).

• Interventions to reduce acute and late adverse gastrointestinal effects of pelvic radiotherapy for primary pelvic… 2018 · Cochrane Headline outcomes only
  RR 2.22 [0.62, 7.93]
  1 study · 110 participants
  Low

Summary of findings: Higher bladder volume vs lower bladder volume

The review found no eligible studies for this question.

• Interventions to reduce acute and late adverse gastrointestinal effects of pelvic radiotherapy for primary pelvic… 2018 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Summary of findings: Higher bladder volume vs lower bladder volume

The review found no eligible studies for this question.

• Interventions to reduce acute and late adverse gastrointestinal effects of pelvic radiotherapy for primary pelvic… 2018 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Higher family income / socioeconomic status vs Lower income / worse socioeconomic status

Higher family income / better socioeconomic status is associated with better OHRQoL in adolescents (narrative synthesis; no pooled estimate or GRADE rating).

• Oral-health-related quality of life in adolescents: umbrella review. 2023 All outcomes

  Community/school/clinic settings; adolescents 10-19 years; included reviews conducted in multiple countries
  Adolescents from families with higher incomes and higher levels of maternal education have better OHRQoL scores [34]. Worse oral health status, older age, female sex and worse socioeconomic status were significantly…
  Studies not reported
  GRADE not reported

Higher circulating 1,25-dihydroxyvitamin D (1,25(OH)2D) concentration vs Lower circulating 1,25-dihydroxyvitamin D (1,25(OH)2D) concentration

The meta-analysis of observational studies reported a OR of 0.99 (95% CI 0.87 to 1.12) for higher versus lower circulating vitamin D concentration.

• Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of observational… 2014 All outcomes
  OR 0.99 [0.87, 1.14]
  7 studies · 3640 participants
  GRADE not reported

Higher circulating 1,25-dihydroxyvitamin D (1,25(OH)2D) concentration vs Lower circulating 1,25-dihydroxyvitamin D (1,25(OH)2D) concentration

The meta-analysis of observational studies reported a OR of 0.99 (95% CI 0.68 to 1.47) for higher versus lower circulating vitamin D concentration.

• Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of observational… 2014 All outcomes
  OR 0.99 [0.68, 1.44]
  3 studies · 3627 participants
  GRADE not reported

Higher BMI (continuous / per-unit increment) vs Lower BMI (continuous reference / per 1 kg/m2 decrement)

Pooling studies that used BMI as a continuous variable showed no significant association between per-unit BMI and childhood dental caries (OR 1.01, 95% CI 0.99 to 1.03; I2=3.5%); ungraded.

• Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… 2024 All outcomes

  Dental examinations of children; 15 countries across Europe, Asia, the Americas and Oceania · Continuous BMI, direct pooling (studies reporting BMI as a continuous variable)
  OR 1.01 [0.99, 1.03]
  4 studies
  GRADE not reported
• Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… 2024 All outcomes

  Dental examinations of children; 15 countries across Europe, Asia, the Americas and Oceania · Non-linear dose-response (restricted cubic splines)
  Fig. 5: significant non-linear (restricted cubic spline) dose-response between BMI and childhood dental caries; relative risk rises at higher BMI (curve reaches ~2.4-2.9 at BMI 30-35) and is also elevated among…
  Studies not reported
  GRADE not reported
• Childhood obesity in relation to risk of dental caries: a cumulative and dose-response systematic review and… 2024 All outcomes

  Dental examinations of children; 15 countries across Europe, Asia, the Americas and Oceania · Linear dose-response (GLST, per 1 kg/m2 BMI increment)
  OR 1.01 [1.00, 1.03]
  16 studies
  GRADE not reported

Higher consumption of snacks / sugar / soft drinks vs Lower consumption

Higher snacking and soft-drink/sugar consumption were associated with more caries in most studies, though one study found no association with sweet-consumption frequency (narrative synthesis; not GRADE-rated).

• Oral Health of Children and Adolescents in the United Arab Emirates: A Systematic Review of the Past Decade. 2021 All outcomes

  UAE; schools (Ajman, Sharjah), nurseries (Ras Al Khaimah)
  Soft drink consumption (Khadri et al.: 0.31, 95% CI 0.14-0.47) and a high extent of snacking (Hashim et al.: high vs low snack level aRR 1.46, 95% CI 1.26-1.70; snacking >=3x vs once daily aRR 1.25, 1.00-1.57) were…
  Studies not reported
  GRADE not reported

Higher threshold (500 mL per six hours or greater) vs lower threshold (less than 500 mL per six hours) at time of aspiration

It is very uncertain whether higher threshold (500 mL per six hours or greater) changes mortality (at the end of compared with lower threshold (less than 500 mL per six hours) at time of aspiration (very low certainty).

• Monitoring of gastric residual volume during enteral nutrition 2021 · Cochrane Headline outcomes only
  RR 1.01 [0.74, 1.38]
  1 study · 322 participants
  Very low

Higher threshold (500 mL per six hours or greater) vs lower threshold (less than 500 mL per six hours) at time of aspiration

It is very uncertain whether higher threshold (500 mL per six hours or greater) changes pneumonia (until discontinued or up to 28 days) compared with lower threshold (less than 500 mL per six hours) at time of aspiration (very low certainty).

• Monitoring of gastric residual volume during enteral nutrition 2021 · Cochrane Headline outcomes only
  RR 1.03 [0.72, 1.46]
  1 study · 322 participants
  Very low

Higher threshold (500 mL per six hours or greater) vs lower threshold (less than 500 mL per six hours) at time of aspiration

• Monitoring of gastric residual volume during enteral nutrition 2021 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 322 participants
  Very low

Higher per-capita expenditure on dental health care vs Lower per-capita expenditure on dental health care (USD bands: $0-50 / $51-100 / >$100)

Countries with higher per-capita dental expenditure had lower mean DMFT (>$100: 0.96; $51-100: 2.14; $0-50: 3.06) (Figure 4); not GRADE-rated.

• Caries status in 12-year-old children, geographical location and socioeconomic conditions across European countries: A… 2025 All outcomes

  Cross-sectional (survey data 2011-2022) · European countries stratified by OECD per-capita dental health-care expenditure (USD); test of group differences Q_b(2)=30.51, p<0.01; expenditure-stratified overall pooled DMFT 2.10 (95% CI 1.61-2.59), 32 countries · $0-50 per capita
  MEAN 3.06 [2.32, 3.79]
  14 studies
  GRADE not reported
• Caries status in 12-year-old children, geographical location and socioeconomic conditions across European countries: A… 2025 All outcomes

  Cross-sectional (survey data 2011-2022) · European countries stratified by OECD per-capita dental health-care expenditure (USD); test of group differences Q_b(2)=30.51, p<0.01; expenditure-stratified overall pooled DMFT 2.10 (95% CI 1.61-2.59), 32 countries · >$100 per capita
  MEAN 0.96 [0.64, 1.28]
  12 studies
  GRADE not reported
• Caries status in 12-year-old children, geographical location and socioeconomic conditions across European countries: A… 2025 All outcomes

  Cross-sectional (survey data 2011-2022) · European countries stratified by OECD per-capita dental health-care expenditure (USD); test of group differences Q_b(2)=30.51, p<0.01; expenditure-stratified overall pooled DMFT 2.10 (95% CI 1.61-2.59), 32 countries · $51-100 per capita
  MEAN 2.14 [1.40, 2.89]
  6 studies
  GRADE not reported

Keratinocyte growth factor (KGF), higher dose/regimen vs Keratinocyte growth factor (KGF), different (lower) dose/regimen

• Interventions for preventing oral mucositis in patients with cancer receiving treatment: cytokines and growth factors 2017 · Cochrane All outcomes
  Some inconsistent evidence from which no conclusions can be drawn regarding different dosages of KGF (Analyses 2.1 to 2.8); no pooled estimate reported
  Studies not reported
  GRADE not reported

Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration

Meta-analysis of observational studies (higher vs lower 25(OH)D) for Prostate cancer: OR 1.04 (95% CI 0.98 to 1.09), not statistically significant. Umbrella review outcome-level evidence grade: Substantial effect unlikely.

• Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of observational… 2014 All outcomes
  OR 1.04 [0.98, 1.09]
  14 studies · 28988 participants
  GRADE not reported

Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration

Meta-analysis of observational studies (higher vs lower 25(OH)D) for Type 2 diabetes: OR 0.63 (95% CI 0.56 to 0.69), statistically significant. Umbrella review outcome-level evidence grade: Suggestive.

• Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of observational… 2014 All outcomes
  OR 0.63 [0.56, 0.69]
  16 studies · 72204 participants
  GRADE not reported

Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration

Meta-analysis of observational studies (higher vs lower 25(OH)D) for Sporadic colorectal adenoma recurrence: OR 0.87 (95% CI 0.57 to 1.33), not statistically significant. Umbrella review outcome-level evidence grade: No conclusion.

• Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of observational… 2014 All outcomes
  OR 0.87 [0.57, 1.33]
  3 studies · 1366 participants
  GRADE not reported

Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration

Meta-analysis of observational studies (higher vs lower 25(OH)D) for Ischaemic heart disease: HR 0.72 (95% CI 0.65 to 0.81), statistically significant. Umbrella review outcome-level evidence grade: No conclusion.

• Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of observational… 2014 All outcomes
  HR 0.72 [0.65, 0.81]
  19 studies · 82982 participants
  GRADE not reported

Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration

Meta-analysis of observational studies (higher vs lower 25(OH)D) for Breast cancer (Premenopausal): RR 1.01 (95% CI 0.97 to 1.06), not statistically significant. Umbrella review outcome-level evidence grade: Substantial effect unlikely.

• Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of observational… 2014 All outcomes

  Premenopausal
  RR 1.01 [0.97, 1.06]
  6 studies · 2890 participants
  GRADE not reported
• Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of observational… 2014 All outcomes

  Postmenopausal
  RR 0.99 [0.97, 1.01]
  9 studies · 8766 participants
  GRADE not reported
• Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of observational… 2014 All outcomes
  OR 0.55 [0.42, 0.71]
  21 studies · 26317 participants
  GRADE not reported