What do systematic reviews say?

Summary of findings table 8: Comfrey root extract vs placebo

• Herbal medicine for low‐back pain 2014 · Cochrane Headline outcomes only
  no estimate extracted
  120 participants
  Low

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 Depression (Cohort studies): HR 0.44 (95% CI 0.27 to 0.72), 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

  Cohort studies
  HR 0.44 [0.27, 0.72]
  3 studies · 8815 participants
  GRADE not reported
• Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of observational… 2014 All outcomes

  Case-control studies
  OR 0.77 [0.59, 1.00]
  9 studies · 19807 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

Meta-analysis of observational studies (higher vs lower 1,25(OH)2D) for Breast cancer: OR 0.99 (95% CI 0.68 to 1.44), 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 0.99 [0.68, 1.44]
  3 studies · 3627 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 stroke (Hazard ratio (cohort studies)): HR 0.66 (95% CI 0.55 to 0.80), 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

  Hazard ratio (cohort studies)
  HR 0.66 [0.55, 0.80]
  4 studies · 26596 participants
  GRADE not reported
• Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of observational… 2014 All outcomes

  Odds ratio (case-control studies)
  OR 0.52 [0.44, 0.61]
  5 studies · 31858 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

Meta-analysis of observational studies (higher vs lower 1,25(OH)2D) for Colon cancer: OR 0.88 (95% CI 0.57 to 1.35), 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 0.88 [0.57, 1.35]
  4 studies
  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

Meta-analysis of observational studies (higher vs lower 1,25(OH)2D) for Aggressive prostate cancer: OR 0.75 (95% CI 0.48 to 1.17), 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 0.75 [0.48, 1.17]
  2 studies · 1488 participants
  GRADE not reported

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

Meta-analysis of observational studies (higher vs lower maternal 25(OH)D) for Gestational diabetes: OR 0.67 (95% CI 0.53 to 0.85), 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 0.67 [0.53, 0.85]
  10 studies · 4112 participants
  GRADE not reported

Frankel's function regulator-4 (FR-4) with lip-seal training vs no treatment

The review found no eligible studies for this question.

• Orthodontic and orthopaedic treatment for anterior open bite in children 2014 · Cochrane All outcomes
  Outcome proposed in the review but not found in any included study. The review states: 'The other outcomes proposed in this review were not found: stability of anterior open bite correction; reduction of snoring; signs…
  0 studies
  No studies found

Repelling-magnet splints vs Bite-blocks

• Orthodontic and orthopaedic treatment for anterior open bite in children 2014 · Cochrane All outcomes

  About 4 months (treatment interrupted early)
  Could not be analysed statistically. After 4 months the open bite was observed to close in the magnet group, but in four out of these ten patients transverse problems (unilateral crossbite) were observed, which led to…
  1 study
  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

Meta-analysis of observational studies (higher vs lower 1,25(OH)2D) for Prostate cancer: OR 0.99 (95% CI 0.87 to 1.14), 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 0.99 [0.87, 1.14]
  7 studies · 3640 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 Kidney cancer: OR 1.01 (95% CI 0.65 to 1.58), 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 1.01 [0.65, 1.58]
  6 studies · 1480 participants
  GRADE not reported

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

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.

• Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of observational… 2014 All outcomes
  SMD (to OR) 0.31 [0.23, 0.42]
  28 studies · 2956 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 Body mass index: Z score -0.15 (95% CI -0.19 to -0.11), 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
  Z score -0.15 [-0.19, -0.11]
  37 studies · 16525 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: OR 0.82 (95% CI 0.69 to 0.97), 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 0.82 [0.69, 0.97]
  9 studies · 6268 participants
  GRADE not reported

Removable appliance with palatal crib associated with high-pull chincup vs no treatment

• Orthodontic and orthopaedic treatment for anterior open bite in children 2014 · Cochrane All outcomes

  End of treatment (12 months)
  The author reported that data (1.NA, 1-NA, 1-PP, 1.NB, 1-NB, 1-GoMe) showed a statistically significant difference. There was palatal inclination of the upper incisors in the intervention group that contributed to…
  1 study
  GRADE not reported

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

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.

• Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of observational… 2014 All outcomes
  RR 0.86 [0.81, 0.92]
  10 studies · 6853 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 (prevalent): OR 0.45 (95% CI 0.25 to 0.82), 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 0.45 [0.25, 0.82]
  9 studies · 11892 participants
  GRADE not reported

Frankel's function regulator-4 (FR-4) with lip-seal training vs no treatment

The review found no eligible studies for this question.

• Orthodontic and orthopaedic treatment for anterior open bite in children 2014 · Cochrane All outcomes
  Outcome proposed in the review but not found in any included study. The review states: 'The other outcomes proposed in this review were not found: stability of anterior open bite correction; reduction of snoring; signs…
  0 studies
  No studies found

Removable appliance with palatal crib associated with high-pull chincup vs no treatment

Removable appliance with palatal crib associated with high-pull… led to lower failure to correct the anterior open bite (open bite not closed) compared with no treatment; GRADE not reported.

• Orthodontic and orthopaedic treatment for anterior open bite in children 2014 · Cochrane All outcomes

  End of treatment (12 months)
  RR 0.23 [0.11, 0.48]
  1 study · 60 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 All cause mortality: HR 0.72 (95% CI 0.66 to 0.78), 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 [0.66, 0.78]
  18 studies · 77155 participants
  GRADE not reported