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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.
5,762 questions in 263 reviews · Dental caries
current versionsNo studies 321 · 5.6%Ungraded 4,450 · 77.2%Very low 455 · 7.9%Low 297 · 5.2%Moderate 200 · 3.5%High 39 · 0.7%
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.
| Question | Effect | Evidence | Status / GRADE |
|---|---|---|---|
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 participants | Ungraded |
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 studies | Ungraded |
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 participants | Ungraded |
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 participants | Ungraded |
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 studies | Ungraded |
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 studies | Ungraded |
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 studies | Ungraded |
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 studies | Ungraded |
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 participants | Ungraded |
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 participants | Ungraded |
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 participants | Ungraded |
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 studies | Ungraded |
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 participants | Ungraded |
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 participants | Ungraded |
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 studies | Ungraded |
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 participants | Ungraded |
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 participants | Ungraded |
Higher circulating 25OHD concentration vs Lower circulating 25OHD concentration Fractures · Participants in observational studies Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | SMD (to OR) 0.31 [0.23, 0.42] | 28 studies · 2956 participants | Ungraded |
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 studies | Ungraded |
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 participants | Ungraded |
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 participants | Ungraded |
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 studies | Ungraded |
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 studies | Ungraded |
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 participants | Ungraded |
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 studies | Ungraded |
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 participants | Ungraded |
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 participants | Ungraded |
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 studies | Ungraded |
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 studies | Ungraded |
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 studies | Ungraded |
Repair of a defective resin composite restoration in a permanent molar or premolar tooth (with resin composite) vs Replacement of a defective resin composite restoration in a permanent molar or premolar tooth (with resin composite) Perioperative or postoperative pain or discomfort · Adults (16 years or over) with one or more defective resin composite restoration(s) in a molar or premolar tooth/teeth · Medium term (less than 5 years) or long term (5 years and above) Replacement versus repair of defective restorations in adults: resin composite (2014) · Cochrane | No randomised controlled trials were found | 0 studies | No studies |
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 participants | Ungraded |
Repair of a defective resin composite restoration in a permanent molar or premolar tooth (with resin composite) vs Replacement of a defective resin composite restoration in a permanent molar or premolar tooth (with resin composite) Extraction of tooth (due to decay) · Adults (16 years or over) with one or more defective resin composite restoration(s) in a molar or premolar tooth/teeth · Medium term (less than 5 years) or long term (5 years and above) Replacement versus repair of defective restorations in adults: resin composite (2014) · Cochrane | No randomised controlled trials were found | 0 studies | No studies |
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 studies | Ungraded |
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 studies | Ungraded |
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 studies | Ungraded |
Repair of a defective amalgam restoration in a permanent molar or premolar tooth (with amalgam) vs Replacement of a defective amalgam restoration in a permanent molar or premolar tooth (with amalgam) Presence of clinical symptoms (pain, swelling, diagnosis of pulpitis, abscess formation) · Adults (16 years or over) with one or more defective amalgam restoration(s) in a molar or premolar tooth/teeth · Medium term (less than 5 years) or long term (5 years and above) Replacement versus repair of defective restorations in adults: amalgam (2014) · Cochrane | No randomised controlled trials were found | 0 studies | No studies |
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 participants | Ungraded |
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 studies | Ungraded |
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 studies | Ungraded |
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 studies | Ungraded |
Vitamin D supplementation vs Placebo or control Dental caries · Children Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.53 [0.43, 0.65] | 38 studies · 1513 participants | Ungraded |
Higher circulating 25OHD concentration vs Lower circulating 25OHD concentration All cause mortality (in CKD patients) · Participants in observational studies Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.86 [0.81, 0.92] | 10 studies · 6853 participants | Ungraded |
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 studies | Ungraded |
Repair of a defective amalgam restoration in a permanent molar or premolar tooth (with amalgam) vs Replacement of a defective amalgam restoration in a permanent molar or premolar tooth (with amalgam) Further restoration required (repair, restoration, placement of crown/inlay, root filling) · Adults (16 years or over) with one or more defective amalgam restoration(s) in a molar or premolar tooth/teeth · Medium term (less than 5 years) or long term (5 years and above) Replacement versus repair of defective restorations in adults: amalgam (2014) · Cochrane | No randomised controlled trials were found | 0 studies | No studies |
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 participants | Ungraded |
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 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration All cause mortality · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | HR 0.72 [0.66, 0.78] | 18 studies · 77155 participants | Ungraded |
Repair of a defective resin composite restoration in a permanent molar or premolar tooth (with resin composite) vs Replacement of a defective resin composite restoration in a permanent molar or premolar tooth (with resin composite) Patient satisfaction (measured by patient satisfaction or aesthetic scales) · Adults (16 years or over) with one or more defective resin composite restoration(s) in a molar or premolar tooth/teeth · Medium term (less than 5 years) or long term (5 years and above) Replacement versus repair of defective restorations in adults: resin composite (2014) · Cochrane | No randomised controlled trials were found | 0 studies | No studies |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Rectal cancer · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.50 [0.29, 0.88] | 9 studies · 2050 participants | Ungraded |