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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 |
|---|---|---|---|
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Pancreatic cancer · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 2.13 [1.02, 4.47] | 6 studies · 2113 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Hip fracture · Adults (general population) · Population-based controls Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | log ratio of geometric mean -0.51 [-0.64, -0.38] | 9 studies · 1655 participants | 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) Patient satisfaction (measured by patient satisfaction or aesthetic scales) · 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 Non-Hodgkin's lymphoma · Adults (general population) · Females Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.81 [0.39, 1.70] | 4 studies · 39 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Hypertension · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.70 [0.58, 0.86] | 7 studies · 48633 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Aggressive prostate cancer · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.98 [0.84, 1.15] | 6 studies · 4524 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Cardiovascular disease mortality · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.55 [0.36, 0.85] | 5 studies · 24387 participants | Ungraded |
Higher maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration Birth length · Pregnant women and their offspring Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD 0.19 [-0.26, 0.65] | 2 studies · 840 participants | Ungraded |
Vitamin D compounds (supplementation) vs Placebo or control Subperiosteal erosions · Adults with chronic kidney disease requiring dialysis Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.41 [0.07, 2.38] | 3 studies · 120 participants | Ungraded |
Vitamin D compounds (supplementation) vs Placebo or control Mortality · 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 1.40 [0.38, 5.15] | 4 studies · 381 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 Colorectal cancer · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 1.01 [0.59, 1.73] | 4 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) Success or failure of restoration (as defined by the USPHS criteria) · 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 Cardiovascular disease (prevalent) · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.67 [0.55, 0.82] | 16 studies · 64722 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Small for gestational age · Pregnant women Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.67 [0.40, 1.11] | 2 studies · 305 participants | Ungraded |
Vitamin D compounds (supplementation) vs Placebo or control Creatinine clearance · 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 -1.68 [-6.92, 3.56] | 4 studies | Ungraded |
Vitamin D compounds (supplementation) vs Placebo or control Risk of hyperphosphataemia · Adults with chronic kidney disease requiring dialysis Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 1.57 [0.97, 2.54] | 2 studies · 59 participants | Ungraded |
Vitamin D compounds (supplementation) vs Placebo or control Fractures · Adults with chronic kidney disease requiring dialysis Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 1.00 [0.06, 15.41] | 4 studies | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Breast cancer · Adults (general population) · Postmenopausal Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.99 [0.97, 1.01] | 9 studies · 8766 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) Adverse events · 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 hypercalcaemia · 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 3.04 [1.17, 7.90] | 7 studies · 612 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Bone mineral density in forearm · Children Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | SMD 0.04 [-0.36, 0.45] | 3 studies | Ungraded |
Higher circulating 25OHD concentration vs Lower circulating 25OHD concentration Tuberculosis · Participants in observational studies Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | SMD (to OR) 0.29 [0.19, 0.46] | 7 studies · 534 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Preterm delivery · Pregnant women Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.77 [0.35, 1.66] | 2 studies · 529 participants | Ungraded |
Higher maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower maternal circulating 25-hydroxyvitamin D (25(OH)D) concentration Birth weight · Pregnant women and their offspring Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD 130.9 [75.1, 186.7] | 4 studies · 5541 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Fractures: vertebral or deformity · Older or community-dwelling adults Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.90 [0.42, 1.92] | 5 studies · 9138 participants | Ungraded |
Vitamin D supplementation vs Control Bone mineral density in forearm · 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 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Ovarian cancer · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.83 [0.63, 1.09] | 10 studies · 2489 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Stroke · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | RR 0.61 [0.50, 0.75] | 7 studies · 39095 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Fasting glucose · Adults with diabetes · Diabetes patients with abnormal glucose tolerance Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD -0.3 [-0.9, 0.3] | NR | Ungraded |
Higher circulating 1,25(OH)2D concentration vs Lower circulating 1,25(OH)2D concentration Breast cancer · Participants in observational studies 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 |
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) Perioperative or postoperative pain or discomfort · 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 Breast cancer · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.55 [0.42, 0.71] | 21 studies · 26317 participants | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Colon cancer · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | OR 0.78 [0.56, 1.07] | 10 studies · 4578 participants | Ungraded |
Vitamin D supplementation vs Placebo or control Total cholesterol · Adults (general population) Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD 1.52 [-1.42, 4.46] | 11 studies | Ungraded |
Vitamin D compounds (supplementation) vs Placebo or control Parathyroid hormone · Adults with chronic kidney disease requiring dialysis Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | WMD -196.05 [-298.43, -93.66] | 6 studies | Ungraded |
Higher circulating 25-hydroxyvitamin D (25(OH)D) concentration vs Lower circulating 25-hydroxyvitamin D (25(OH)D) concentration Hip fracture · Adults (general population) · Hospital-based controls Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of… (2014) | log ratio of geometric mean -0.26 [-0.33, -0.23] | 8 studies · 2201 participants | Ungraded |
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 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) Further restoration required (repair, restoration, placement of crown/inlay, root filling) · 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 |
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) Success or failure of restoration (as defined by the USPHS criteria) · 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 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 participants | Ungraded |
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 studies | Ungraded |
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 participants | Ungraded |
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 studies | Ungraded |
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 studies | Ungraded |
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 participants | Ungraded |
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 participants | 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) Extraction of tooth (due to decay) · 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 |
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) Adverse events · 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) · 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 participants | Ungraded |
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 participants | Ungraded |