evidencegaps
Findings

What do systematic reviews say?

Refine by population, intervention, comparison or outcome
More filters
Evidence found and GRADE certainty

3,372 questions · 3,874 findings · 666 reviews

Sort:Best matchNewestHighest certaintyDownload CSV
No studies found 431 · 11.1%GRADE not reported 783 · 20.2%Very low 995 · 25.7%Low 909 · 23.5%Moderate 596 · 15.4%High 160 · 4.1%

Monthly pulsed high‐dose dexamethasone vs prednisolone

≥ 1 point improvement on INCAT disability score at 12 months · patients with chronic inflammatory demyelinating polyradiculoneuropathy

Monthly pulsed high‐dose dexamethasone may leads to higher ≥ 1 point improvement on INCAT disability score at 12 months compared with oral prednisolone (low certainty).

1 finding from 1 review

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

Alzheimer’s disease · Participants in observational studies

The meta-analysis of observational studies reported a SMD (to OR) of 0.08 (95% CI 0.01 to 0.63) for higher versus lower circulating vitamin D concentration.

1 finding from 1 review

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

Aggressive prostate cancer · Participants in observational studies

The meta-analysis of observational studies reported a OR of 0.88 (95% CI 0.68 to 1.15) for higher versus lower circulating vitamin D concentration.

1 finding from 1 review

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

Tuberculosis · Participants in observational studies

The meta-analysis of observational studies reported a SMD (to OR) of 0.29 (95% CI 0.19 to 0.46) for higher versus lower circulating vitamin D concentration.

1 finding from 1 review

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

Fracture · Participants in observational studies

The meta-analysis of observational studies reported a SMD (to OR) of 0.31 (95% CI 0.23 to 0.42) for higher versus lower circulating vitamin D concentration.

1 finding from 1 review

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

All cause mortality (in CKD patients) · Participants in observational studies

The meta-analysis of observational studies reported a RR of 0.88 (95% CI 0.81 to 0.93) for higher versus lower circulating vitamin D concentration.

1 finding from 1 review

Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference)

Fracture · general population

Non-linear positive dose-response: little change in overall fracture risk below ~1.5 mg/L drinking-water fluoride, with risk increasing above that threshold (RR 1.06, 1.19, 1.35 at 2.0, 3.0, 4.0 mg/L vs null); ungraded (4 studies).

4 findings from 1 review
Show 1 more finding

Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference)

Risk of femoral fractures · general population

Femoral-fracture risk was mildly U-shaped: RR 0.86 at 0.5 mg/L rising to 1.06 at 1.8 mg/L drinking-water fluoride vs null; risk mostly below null across the range; ungraded.

2 findings from 1 review
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Drinking-water fluoride 1.8 mg/L vs null
    RR 1.06 [0.67, 1.69]
    Studies not reported
    GRADE not reported
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Drinking-water fluoride 0.5 mg/L vs null
    RR 0.86 [0.71, 1.05]
    Studies not reported
    GRADE not reported

Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference)

Risk of fragility fractures · Male participants

In males (7 studies), fragility-fracture risk generally decreased with increasing fluoride: RR 0.83 (95% CI 0.72-0.97) at 0.57 mg/L to 0.87 (0.48-1.58) at 1.8 mg/L vs null; ungraded.

2 findings from 1 review
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Males: drinking-water fluoride 1.8 mg/L vs null
    RR 0.87 [0.48, 1.58]
    7 studies
    GRADE not reported
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Males: drinking-water fluoride 0.57 mg/L vs null
    RR 0.83 [0.72, 0.97]
    7 studies
    GRADE not reported

Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference)

Risk of fragility fractures · general population

Fragility-fracture risk overall was slightly U-shaped: RR 0.93 up to 0.9 mg/L, ~1.00 at 1.48 mg/L, 1.05 at 1.8 mg/L drinking-water fluoride vs null; ungraded.

5 findings from 1 review
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Drinking-water fluoride up to 0.9 mg/L vs null
    RR 0.93 [0.84, 1.02]
    Studies not reported
    GRADE not reported
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Drinking-water fluoride 1.8 mg/L vs null
    RR 1.05 [0.82, 1.35]
    Studies not reported
    GRADE not reported
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Sensitivity (excluding high risk-of-bias studies): 0.8-1.5 mg/L vs null
    RR 0.93 [0.72, 1.21]
    Studies not reported
    GRADE not reported
Show 2 more findings
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Drinking-water fluoride 1.48 mg/L vs null
    RR 1.00 [0.82, 1.21]
    Studies not reported
    GRADE not reported
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Sensitivity (excluding high risk-of-bias studies): 1.8 mg/L vs null
    RR 0.95 [0.70, 1.29]
    Studies not reported
    GRADE not reported

Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference)

Lumbar spine bone mineral density (BMD) · general population

Spine BMD showed an inverted U-shaped association with fluoride (peak ~0.6 mg/L); excluding high risk-of-bias studies gave small positive MDs (e.g., 0.05 g/cm2, 95% CI 0.01-0.10, up to 2.27 mg/L); ungraded.

4 findings from 1 review
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Sensitivity (excluding high risk-of-bias studies): 1.27 to 2.27 mg/L vs null
    MD 0.05 [0.01, 0.10]
    Studies not reported
    GRADE not reported
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Sensitivity (excluding high risk-of-bias studies): 0.60 mg/L vs null
    MD 0.06 [-0.02, 0.13]
    Studies not reported
    GRADE not reported
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Both sexes, main dose-response
    Inverted U-shaped association in both males and females, highest value around 0.6 mg/L (no numeric MD reported in text for main analysis)
    Studies not reported
    GRADE not reported
Show 1 more finding
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Sensitivity (excluding high risk-of-bias studies): above 2.27 mg/L vs null
    MD 0.04 [-0.21, 0.30]
    Studies not reported
    GRADE not reported