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Search review questions

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.

Limit to evidence status or GRADE (optional)

102 questions in 1 reviews · cluster CL0346

current versions
No studies 0 · 0%Ungraded 102 · 100%Very low 0 · 0%Low 0 · 0%Moderate 0 · 0%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

QuestionEffectEvidenceStatus / GRADE
Vitamin D compounds (supplementation) vs Placebo or control
Risk of requiring dialysis · Adults with chronic kidney disease not requiring dialysis
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
RR 0.76 [0.36, 1.62]4 studies · 245 participantsUngraded
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration
Colorectal cancer · Adults (general population)
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
RR 0.70 [0.58, 0.84]10 studies · 6712 participantsUngraded
Vitamin D compounds (supplementation) vs Placebo or control
Parathyroid hormone · Adults with chronic kidney disease not requiring dialysis
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
WMD -49.34 [-85.70, -12.97]4 studiesUngraded
Vitamin D supplementation vs Placebo or control
Mortality (all cause) · Adults (general population) · Vitamin D2, general population
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
RR 1.04 [0.97, 1.11]8 studies · 17079 participantsUngraded
Vitamin D supplementation vs Placebo or control
Performance measures: balance sway · Older or community-dwelling adults
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
SMD -0.20 [-0.39, -0.01]3 studiesUngraded
Vitamin D supplementation vs Placebo or control
Performance measures: lower extremity strength · Older or community-dwelling adults
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
SMD 0.05 [-0.11, 0.20]3 studiesUngraded
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration
Cardiovascular disease · Adults (general population)
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
RR 0.66 [0.57, 0.77]19 studies · 66488 participantsUngraded
Vitamin D supplementation vs Placebo or control
Mortality (all cause) · Adults (general population) · Vitamin D3, general population
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
RR 0.91 [0.82, 1.02]9 studies · 12824 participantsUngraded
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration
Depression · Adults (general population) · Cohort studies
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
HR 0.44 [0.27, 0.72]3 studies · 8815 participantsUngraded
Vitamin D compounds (supplementation) vs Placebo or control
Vascular calcification · Adults with chronic kidney disease requiring dialysis
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
RR 1.09 [0.45, 2.67]2 studies · 128 participantsUngraded
Vitamin D compounds (supplementation) vs Placebo or control
Mortality · Adults with chronic kidney disease requiring dialysis
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
RR 1.34 [0.34, 5.24]5 studies · 477 participantsUngraded
Vitamin D supplementation vs Placebo or control
Triglycerides · Adults (general population)
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
WMD -1.92 [-7.72, 3.88]8 studiesUngraded
Higher circulating 1,25-dihydroxyvitamin D (1,25(OH)2D) concentration vs Lower circulating 1,25-dihydroxyvitamin D (1,25(OH)2D) concentration
Breast cancer · Adults (general population)
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
OR 0.99 [0.68, 1.44]3 studies · 3627 participantsUngraded
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration
Ischaemic stroke · Adults (general population) · Hazard ratio (cohort studies)
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
HR 0.66 [0.55, 0.80]4 studies · 26596 participantsUngraded
Vitamin D supplementation vs Placebo or control
High density lipoprotein · Adults (general population)
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
WMD -0.14 [-0.99, 0.71]8 studiesUngraded
Higher circulating 1,25-dihydroxyvitamin D (1,25(OH)2D) concentration vs Lower circulating 1,25-dihydroxyvitamin D (1,25(OH)2D) concentration
Colon cancer · Adults (general population)
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
OR 0.88 [0.57, 1.35]4 studiesUngraded
Vitamin D supplementation vs Placebo or control
Falls · Older or community-dwelling adults
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
OR 0.97 [0.84, 1.11]10 studiesUngraded
Vitamin D supplementation vs Placebo or control
Head circumference at birth · Pregnant women
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
WMD 0.43 [0.06, 0.79]2 studiesUngraded
Vitamin D supplementation vs Placebo or control
Low birth weight · Pregnant women
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
RR 0.4 [0.23, 0.71]3 studies · 507 participantsUngraded
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration
Ischaemic stroke · Adults (general population) · Odds ratio (case-control studies)
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
OR 0.52 [0.44, 0.61]5 studies · 31858 participantsUngraded
Higher circulating 1,25-dihydroxyvitamin D (1,25(OH)2D) concentration vs Lower circulating 1,25-dihydroxyvitamin D (1,25(OH)2D) concentration
Aggressive prostate cancer · Adults (general population)
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
OR 0.75 [0.48, 1.17]2 studies · 1488 participantsUngraded
Vitamin D compounds (supplementation) vs Placebo or control
Alkaline phosphatase · Adults with chronic kidney disease requiring dialysis
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
WMD -27.35 [-50.69, -4.01]3 studiesUngraded
Higher maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration
Gestational diabetes · Pregnant women and their offspring
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
OR 0.67 [0.53, 0.85]10 studies · 4112 participantsUngraded
Vitamin D supplementation vs Placebo or control
Fractures · Older or community-dwelling adults
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
RR 1.01 [0.93, 1.09]10 studies · 25016 participantsUngraded
Vitamin D supplementation vs Placebo or control
Bone mineral density in forearm · Older or community-dwelling adults
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
WMD -0.70 [-1.70, 0.40]2 studiesUngraded
Higher circulating 1,25-dihydroxyvitamin D (1,25(OH)2D) concentration vs Lower circulating 1,25-dihydroxyvitamin D (1,25(OH)2D) concentration
Prostate cancer · Adults (general population)
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
OR 0.99 [0.87, 1.14]7 studies · 3640 participantsUngraded
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration
Kidney cancer · Adults (general population)
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
OR 1.01 [0.65, 1.58]6 studies · 1480 participantsUngraded
Vitamin D supplementation vs Placebo or control
Bone mineral density in hip · Older or community-dwelling adults
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
WMD 0.70 [-0.10, 1.60]6 studiesUngraded
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration
Non-Hodgkin's lymphoma · Adults (general population) · Males
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
OR 0.65 [0.35, 1.23]6 studies · 65 participantsUngraded
Vitamin D compounds (supplementation) vs Placebo or control
Parathyroidectomy · Adults with chronic kidney disease requiring dialysis
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
RR 0.82 [0.05, 12.47]2 studies · 233 participantsUngraded
Vitamin D supplementation vs Placebo or control
Low density lipoprotein · Adults (general population)
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
WMD 3.23 [0.55, 5.9]7 studiesUngraded
Vitamin D supplementation vs Placebo or control
Cardiovascular disease · Adults (general population)
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
RR 0.95 [0.86, 1.05]2 studiesUngraded
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration
Body mass index · Adults (general population)
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
Z score -0.15 [-0.19, -0.11]37 studies · 16525 participantsUngraded
Vitamin D supplementation vs Placebo or control
Bone mineral density in lumbar spine · Children
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
SMD 0.15 [-0.01, 0.31]5 studiesUngraded
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration
Sporadic colorectal adenoma · Adults (general population)
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
OR 0.82 [0.69, 0.97]9 studies · 6268 participantsUngraded
Vitamin D supplementation vs Placebo or control
Fractures: hip · Older or community-dwelling adults
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
RR 1.15 [0.99, 1.33]9 studies · 24749 participantsUngraded
Vitamin D compounds (supplementation) vs Placebo or control
Alkaline phosphatase · Adults with chronic kidney disease not requiring dialysis
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
WMD -21.81 [-40.39, 3.22]2 studiesUngraded
Vitamin D supplementation vs Placebo or control
Birth length · Pregnant women
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
WMD 0.97 [-0.41, 2.34]2 studiesUngraded
Vitamin D supplementation vs Placebo or control
Systolic blood pressure · Adults (general population)
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
WMD -2.39 [-5.7, 0.9]3 studiesUngraded
Vitamin D compounds (supplementation) vs Placebo or control
Risk of hyperphosphataemia · Adults with chronic kidney disease not requiring dialysis
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
RR 1.58 [0.47, 5.30]2 studies · 245 participantsUngraded
Vitamin D supplementation vs Placebo or control
Maternal vitamin D concentrations at term · Pregnant women
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
WMD 47.08 [23.76, 70.39]4 studiesUngraded
Vitamin D supplementation vs Placebo or control
Bone mineral density · Children · Whole body / total
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
SMD 0.1 [-0.06, 0.26]5 studiesUngraded
Vitamin D supplementation vs Placebo or control
Bone mineral density in hip · Children
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
SMD 0.06 [-0.18, 0.29]4 studiesUngraded
Vitamin D compounds (supplementation) vs Placebo or control
Bone pain · Adults with chronic kidney disease requiring dialysis
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
RR 0.29 [0.03, 2.63]4 studies · 109 participantsUngraded
Vitamin D supplementation vs Placebo or control
Falls: rate of falls · Older or community-dwelling adults · Older people in care facilities or hospitals
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
RAR 0.55 [0.19, 1.64]2 studiesUngraded
Vitamin D supplementation vs Placebo or control
Bone mineral density · Older or community-dwelling adults
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
WMD -0.9 [-2.10, 0.40]3 studiesUngraded
Vitamin D supplementation vs Placebo or control
Falls: rate of falls · Older or community-dwelling adults · Older people in the community
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
RAR 1.14 [1.03, 1.27]2 studiesUngraded
Vitamin D supplementation vs Placebo or control
Insulin resistance · Adults with diabetes · Diabetes
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
SMD 0.16 [-0.11, 0.42]5 studiesUngraded
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration
Depression · Adults (general population) · Case-control studies
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
OR 0.77 [0.59, 1.00]9 studies · 19807 participantsUngraded
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration
Type 2 diabetes (prevalent) · Adults (general population)
Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014)
OR 0.45 [0.25, 0.82]9 studies · 11892 participantsUngraded