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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.
780 questions in 55 reviews · Public Health
current versionsNo studies 162 · 20.8%Ungraded 52 · 6.7%Very low 231 · 29.6%Low 191 · 24.5%Moderate 122 · 15.6%High 22 · 2.8%
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 |
|---|---|---|---|
Summary of findings table ‐ Low‐carbohydrate weight‐reducing diets vs balanced‐carbohydrate weight‐reducing diets Change in body weight (kg) at ≥ 12 months · overweight and obese participants with T2DM (weight‐reducing phase followed by weight‐maintenance phase) Low‐carbohydrate versus balanced‐carbohydrate diets for reducing weight and cardiovascular risk (2022) · Cochrane | no estimate extracted | 3 studies · 158 participants | Low |
Summary of findings table ‐ Low‐carbohydrate weight‐reducing diets vs balanced‐carbohydrate weight‐reducing diets Weight loss of at least 5% at ≥ 12 months ‐ not measured · overweight and obese participants with T2DM (weight‐reducing phase followed by weight‐maintenance phase) Low‐carbohydrate versus balanced‐carbohydrate diets for reducing weight and cardiovascular risk (2022) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings table ‐ Low‐carbohydrate weight‐reducing diets vs balanced‐carbohydrate weight‐reducing diets Cardiovascular mortality ‐ not measured · overweight and obese participants with T2DM (weight‐reducing phase followed by weight‐maintenance phase) Low‐carbohydrate versus balanced‐carbohydrate diets for reducing weight and cardiovascular risk (2022) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings table ‐ Low‐carbohydrate weight‐reducing diets vs balanced‐carbohydrate weight‐reducing diets Change in DBP (mmHg) at ≥ 12 months · overweight and obese participants with T2DM (weight‐reducing phase followed by weight‐maintenance phase) Low‐carbohydrate versus balanced‐carbohydrate diets for reducing weight and cardiovascular risk (2022) · Cochrane | no estimate extracted | 1 study · 99 participants | Very low |
Summary of findings table ‐ Low‐carbohydrate weight‐reducing diets vs balanced‐carbohydrate weight‐reducing diets Change in HbA1c (%) at ≥ 12 months · overweight and obese participants with T2DM (weight‐reducing phase followed by weight‐maintenance phase) Low‐carbohydrate versus balanced‐carbohydrate diets for reducing weight and cardiovascular risk (2022) · Cochrane | no estimate extracted | 3 studies · 160 participants | Low |
Summary of findings table ‐ Low‐carbohydrate weight‐reducing diets vs balanced‐carbohydrate weight‐reducing diets Change in LDL cholesterol (mmol/L) at ≥ 12 months · overweight and obese participants with T2DM (weight‐reducing phase followed by weight‐maintenance phase) Low‐carbohydrate versus balanced‐carbohydrate diets for reducing weight and cardiovascular risk (2022) · Cochrane | no estimate extracted | 2 studies · 145 participants | Low |
Summary of findings table ‐ Low‐carbohydrate weight‐reducing diets vs balanced‐carbohydrate weight‐reducing diets Number of participants per group with weight loss of at least 5% at ≥ 12 months · overweight and obese participants without T2DM (weight‐reducing phase only) Low‐carbohydrate versus balanced‐carbohydrate diets for reducing weight and cardiovascular risk (2022) · Cochrane | RR 1.11 [0.94, 1.31] | 2 studies · 137 participants | Very low |
Summary of findings table ‐ Low‐carbohydrate weight‐reducing diets vs balanced‐carbohydrate weight‐reducing diets Constipation at 3 to < 12 months ‐ not measured · overweight and obese participants with T2DM (weight‐reducing phase followed by weight‐maintenance phase) Low‐carbohydrate versus balanced‐carbohydrate diets for reducing weight and cardiovascular risk (2022) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings table ‐ Low‐carbohydrate weight‐reducing diets vs balanced‐carbohydrate weight‐reducing diets Cardiovascular mortality ‐ not measured · overweight and obese participants without T2DM (weight‐reducing phase only) Low‐carbohydrate versus balanced‐carbohydrate diets for reducing weight and cardiovascular risk (2022) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings table ‐ Low‐carbohydrate weight‐reducing diets vs balanced‐carbohydrate weight‐reducing diets Change in DBP (mmHg) at ≥ 12 months · overweight and obese participants without T2DM (weight‐reducing phase only) Low‐carbohydrate versus balanced‐carbohydrate diets for reducing weight and cardiovascular risk (2022) · Cochrane | no estimate extracted | 11 studies · 1419 participants | Moderate |
Summary of findings table ‐ Low‐carbohydrate weight‐reducing diets vs balanced‐carbohydrate weight‐reducing diets Change in LDL cholesterol (mmol/L) at ≥ 12 months · overweight and obese participants without T2DM (weight‐reducing phase only) Low‐carbohydrate versus balanced‐carbohydrate diets for reducing weight and cardiovascular risk (2022) · Cochrane | no estimate extracted | 13 studies · 1494 participants | Moderate |
Summary of findings table ‐ Low‐carbohydrate weight‐reducing diets vs balanced‐carbohydrate weight‐reducing diets Constipation at 3 to < 12 months · overweight and obese participants without T2DM (weight‐reducing phase only) Low‐carbohydrate versus balanced‐carbohydrate diets for reducing weight and cardiovascular risk (2022) · Cochrane | RR 1.06 [0.81, 1.38] | 4 studies · 564 participants | Very low |
Summary of findings table ‐ Low‐carbohydrate weight‐reducing diets vs balanced‐carbohydrate weight‐reducing diets Change in body weight (kg) at 3 to < 12 months ‐ not measured · overweight and obese participants without T2DM (weight‐reducing phase followed by weight maintenance phase) Low‐carbohydrate versus balanced‐carbohydrate diets for reducing weight and cardiovascular risk (2022) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings table ‐ Low‐carbohydrate weight‐reducing diets vs balanced‐carbohydrate weight‐reducing diets Change in body weight (kg) at ≥ 12 months · overweight and obese participants without T2DM (weight‐reducing phase followed by weight maintenance phase) Low‐carbohydrate versus balanced‐carbohydrate diets for reducing weight and cardiovascular risk (2022) · Cochrane | no estimate extracted | 3 studies · 73 participants | Low |
Summary of findings table ‐ LSSS intervention vs regular salt Change in DBP (mmHg) · adults (≥ 18 years) in the general population Replacing salt with low‐sodium salt substitutes (LSSS) for cardiovascular health in adults, children and… (2022) · Cochrane | no estimate extracted | 19 studies · 20830 participants | Moderate |
Summary of findings table ‐ LSSS intervention vs regular salt Change in blood potassium (mmol/L) · adults (≥ 18 years) in the general population Replacing salt with low‐sodium salt substitutes (LSSS) for cardiovascular health in adults, children and… (2022) · Cochrane | no estimate extracted | 6 studies · 784 participants | Moderate |
Summary of findings table ‐ LSSS intervention vs regular salt Hyperkalaemia · adults (≥ 18 years) in the general population Replacing salt with low‐sodium salt substitutes (LSSS) for cardiovascular health in adults, children and… (2022) · Cochrane | RR 1.04 [0.46, 2.38] | 5 studies · 22849 participants | Moderate |
Summary of findings table ‐ LSSS intervention vs regular salt Hypokalaemia · adults (≥ 18 years) in the general population Replacing salt with low‐sodium salt substitutes (LSSS) for cardiovascular health in adults, children and… (2022) · Cochrane | no estimate extracted | 1 study · 22 participants | Very low |
Summary of findings table ‐ LSSS intervention vs regular salt Adverse events: other · adults (≥ 18 years) in the general population Replacing salt with low‐sodium salt substitutes (LSSS) for cardiovascular health in adults, children and… (2022) · Cochrane | no estimate extracted | 8 studies · 2109 participants | Very low |
Summary of findings table ‐ LSSS intervention vs regular salt Change in DBP (mmHg) · children (2 to < 18 years) in the general population Replacing salt with low‐sodium salt substitutes (LSSS) for cardiovascular health in adults, children and… (2022) · Cochrane | no estimate extracted | 1 study · 92 participants | Very low |
Summary of findings table ‐ LSSS intervention vs regular salt Change in SBP (mmHg) · children (2 to < 18 years) in the general population Replacing salt with low‐sodium salt substitutes (LSSS) for cardiovascular health in adults, children and… (2022) · Cochrane | no estimate extracted | 1 study · 92 participants | Very low |
Summary of findings table ‐ LSSS intervention vs regular salt Hypertension ‐ not measured · children (2 to < 18 years) in the general population Replacing salt with low‐sodium salt substitutes (LSSS) for cardiovascular health in adults, children and… (2022) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings table ‐ LSSS intervention vs regular salt Blood pressure control ‐ not measured · children (2 to < 18 years) in the general population Replacing salt with low‐sodium salt substitutes (LSSS) for cardiovascular health in adults, children and… (2022) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings table ‐ LSSS intervention vs regular salt Change in blood potassium (mmol/L) ‐ not measured · children (2 to < 18 years) in the general population Replacing salt with low‐sodium salt substitutes (LSSS) for cardiovascular health in adults, children and… (2022) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings table ‐ LSSS intervention vs regular salt Hyperkalaemia ‐ not measured · children (2 to < 18 years) in the general population Replacing salt with low‐sodium salt substitutes (LSSS) for cardiovascular health in adults, children and… (2022) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings table ‐ LSSS intervention vs regular salt Change in SBP (mmHg) · adults (≥ 18 years) in the general population Replacing salt with low‐sodium salt substitutes (LSSS) for cardiovascular health in adults, children and… (2022) · Cochrane | no estimate extracted | 20 studies · 21414 participants | Moderate |
Summary of findings table ‐ LSSS intervention vs regular salt Hypokalaemia ‐ not measured · children (2 to < 18 years) in the general population Replacing salt with low‐sodium salt substitutes (LSSS) for cardiovascular health in adults, children and… (2022) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings table ‐ LSSS intervention vs regular salt Hypertension · adults (≥ 18 years) in the general population Replacing salt with low‐sodium salt substitutes (LSSS) for cardiovascular health in adults, children and… (2022) · Cochrane | RR 0.97 [0.9, 1.03] | 1 study · 2566 participants | Low |
Summary of findings table ‐ LSSS intervention vs regular salt Blood pressure control · adults (≥ 18 years) in the general population Replacing salt with low‐sodium salt substitutes (LSSS) for cardiovascular health in adults, children and… (2022) · Cochrane | RR 2.12 [1.32, 3.41] | 2 studies · 253 participants | Very low |
Summary of findings table ‐ LSSS intervention vs regular salt Cardiovascular events: various · adults (≥ 18 years) in the general population Replacing salt with low‐sodium salt substitutes (LSSS) for cardiovascular health in adults, children and… (2022) · Cochrane | RR 1.22 [0.49, 3.04] | 5 studies · 982 participants | Very low |
Summary of findings table ‐ LSSS intervention vs regular salt Cardiovascular events: non‐fatal stroke · adults (≥ 18 years) in the general population Replacing salt with low‐sodium salt substitutes (LSSS) for cardiovascular health in adults, children and… (2022) · Cochrane | RR 0.9 [0.8, 1.01] | 3 studies · 21250 participants | Moderate |
Summary of findings table ‐ LSSS intervention vs regular salt Cardiovascular events: non‐fatal acute coronary syndrome (events per 100,000 person‐years) · adults (≥ 18 years) in the general population Replacing salt with low‐sodium salt substitutes (LSSS) for cardiovascular health in adults, children and… (2022) · Cochrane | Rate ratio 0.7 [0.52, 0.94] | 1 study · 20995 participants | Moderate |
Summary of findings table ‐ LSSS intervention vs regular salt Cardiovascular mortality (events per 100,000 person‐years) · adults (≥ 18 years) in the general population Replacing salt with low‐sodium salt substitutes (LSSS) for cardiovascular health in adults, children and… (2022) · Cochrane | Rate ratio 0.77 [0.6, 1] | 3 studies · 23200 participants | Moderate |
Summary of findings table ‐ LSSS intervention vs regular salt Stroke mortality (events per 100,000 person‐years) · adults (≥ 18 years) in the general population Replacing salt with low‐sodium salt substitutes (LSSS) for cardiovascular health in adults, children and… (2022) · Cochrane | Rate ratio 0.64 [0.33, 1.25] | 2 studies · 21423 participants | Very low |
Intervention NR % of participants physically active [ · children and adolescents aged 6 to 18 years School‐based physical activity programs for promoting physical activity and fitness in children and… (2021) · Cochrane | no estimate extracted | 5 studies · 6068 participants | Very low |
Intervention NR Moderate to vigorous physical activity (minutes/d) [ · children and adolescents aged 6 to 18 years School‐based physical activity programs for promoting physical activity and fitness in children and… (2021) · Cochrane | no estimate extracted | 33 studies · 20614 participants | Moderate |
Intervention NR Sedentary time (minutes/d)[ · children and adolescents aged 6 to 18 years School‐based physical activity programs for promoting physical activity and fitness in children and… (2021) · Cochrane | no estimate extracted | 16 studies · 11914 participants | Low |
Intervention NR Physical fitness (VO₂ max, mL/kg/min)[ · children and adolescents aged 6 to 18 years School‐based physical activity programs for promoting physical activity and fitness in children and… (2021) · Cochrane | no estimate extracted | 13 studies · 3980 participants | Low |
Intervention NR BMI (z‐score)[ · children and adolescents aged 6 to 18 years School‐based physical activity programs for promoting physical activity and fitness in children and… (2021) · Cochrane | no estimate extracted | 21 studies · 22948 participants | Low |
Intervention NR BMI (kg/m²)[ · children and adolescents aged 6 to 18 years School‐based physical activity programs for promoting physical activity and fitness in children and… (2021) · Cochrane | no estimate extracted | 50 studies · 34337 participants | Low |
Intervention NR Health‐related quality of life [ · children and adolescents aged 6 to 18 years School‐based physical activity programs for promoting physical activity and fitness in children and… (2021) · Cochrane | no estimate extracted | 7 studies · 4687 participants | Very low |
Intervention NR Adverse events [ · children and adolescents aged 6 to 18 years School‐based physical activity programs for promoting physical activity and fitness in children and… (2021) · Cochrane | no estimate extracted | 16 studies · 11698 participants | Very low |
iron‐fortified wheat flour with or without other micronutrients added vs wheat flour (no added iron) with the same other micronutrients added Anaemia (defined as haemoglobin below WHO cut‐off for age and adjusted for altitude as appropriate) · general population of all age groups (including pregnant women) from any country, over two years of age Wheat flour fortification with iron and other micronutrients for reducing anaemia and improving iron status… (2021) · Cochrane | RR 0.73 [0.55, 0.97] | 5 studies · 2315 participants | Low |
Iron‐fortified wheat flour with other micronutrients added vs unfortified wheat flour (no micronutrients added) Haemoglobin concentration (g/L) · general population of all age groups (including pregnant women) from any country, over two years of age Wheat flour fortification with iron and other micronutrients for reducing anaemia and improving iron status… (2021) · Cochrane | no estimate extracted | 4 studies · 532 participants | Very low |
Iron‐fortified wheat flour with other micronutrients added vs unfortified wheat flour (no micronutrients added) Diarrhoea (3 liquid stools in a single day) (only in children 2 to 11 years of age) · general population of all age groups (including pregnant women) from any country, over two years of age Wheat flour fortification with iron and other micronutrients for reducing anaemia and improving iron status… (2021) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
Iron‐fortified wheat flour with other micronutrients added vs unfortified wheat flour (no micronutrients added) Respiratory infections (as measured by trialists) (only in children 2 to 11 years of age) · general population of all age groups (including pregnant women) from any country, over two years of age Wheat flour fortification with iron and other micronutrients for reducing anaemia and improving iron status… (2021) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
Iron‐fortified wheat flour with other micronutrients added vs unfortified wheat flour (no micronutrients added) All‐cause death (only in children 2 to 11 years of age) · general population of all age groups (including pregnant women) from any country, over two years of age Wheat flour fortification with iron and other micronutrients for reducing anaemia and improving iron status… (2021) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
Iron‐fortified wheat flour with other micronutrients added vs unfortified wheat flour (no micronutrients added) Infection or inflammation at individual level (as measured by urinary neopterin, C‐reactive protein or alpha‐1‐acid glycoprotein variant A) · general population of all age groups (including pregnant women) from any country, over two years of age Wheat flour fortification with iron and other micronutrients for reducing anaemia and improving iron status… (2021) · Cochrane | no estimate extracted | 0 studies · 0 participants | Ungraded |
iron‐fortified wheat flour with or without other micronutrients added vs wheat flour (no added iron) with the same other micronutrients added Iron deficiency (as defined by study authors, based on a biomarker of iron status) · general population of all age groups (including pregnant women) from any country, over two years of age Wheat flour fortification with iron and other micronutrients for reducing anaemia and improving iron status… (2021) · Cochrane | RR 0.46 [0.2, 1.04] | 3 studies · 748 participants | Very low |
iron‐fortified wheat flour with or without other micronutrients added vs wheat flour (no added iron) with the same other micronutrients added Haemoglobin concentration (g/L) · general population of all age groups (including pregnant women) from any country, over two years of age Wheat flour fortification with iron and other micronutrients for reducing anaemia and improving iron status… (2021) · Cochrane | no estimate extracted | 8 studies · 2831 participants | Very low |