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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 |
|---|---|---|---|
Interventions targeting vehicular sources vs practice Coarse particulate matter · General population Interventions to reduce ambient particulate matter air pollution and their effect on health (2019) · Cochrane | no estimate extracted | NR | No studies |
Interventions targeting vehicular sources vs practice Combustion‐related particulate matter · General population Interventions to reduce ambient particulate matter air pollution and their effect on health (2019) · Cochrane | no estimate extracted | NR | Low |
Interventions targeting industrial sources vs practice All‐cause mortality · General population, as well as age‐specific subgroups (< 1 year; < 14 years; > 65 years) Interventions to reduce ambient particulate matter air pollution and their effect on health (2019) · Cochrane | no estimate extracted | NR | Low |
Interventions targeting industrial sources vs practice Cardiovascular mortality · General population, as well as age‐specific subgroups (< 1 year; < 14 years; > 65 years) Interventions to reduce ambient particulate matter air pollution and their effect on health (2019) · Cochrane | no estimate extracted | NR | Low |
Intervention NR Anaemia Defined as haemoglobin (Hb) concentration < 11 g/dL Measured at after 6 months and 6 ‐ 12 months of intervention · General population Food fortification with multiple micronutrients: impact on health outcomes in general population (2019) · Cochrane | RR 0.68 [0.56, 0.84] | 11 studies · 3746 participants | Low |
Intervention NR Micronutrient deficiencies · General population Food fortification with multiple micronutrients: impact on health outcomes in general population (2019) · Cochrane | RR 0.44 [0.32, 0.6] | 11 studies · 3289 participants | Low |
Intervention NR Anthropometric · General population Food fortification with multiple micronutrients: impact on health outcomes in general population (2019) · Cochrane | no estimate extracted | 8 studies · 2889 participants | Low |
Intervention NR Anaemia Anaemia was defined as a haemoglobin (Hb) concentration < 13 g/dL for boys and < 12 g/dL for girls Measured after 9 months of intervention · General population Food fortification with multiple micronutrients: impact on health outcomes in general population (2019) · Cochrane | RR 0.86 [0.37, 2.01] | 1 study · 88 participants | Very low |
Intervention NR Micronutrient deficiencies · General population Food fortification with multiple micronutrients: impact on health outcomes in general population (2019) · Cochrane | RR 0.98 [0.82, 1.17] | 1 study · 88 participants | Very low |
Intervention NR Anthropometric outcomes · General population Food fortification with multiple micronutrients: impact on health outcomes in general population (2019) · Cochrane | no estimate extracted | NR | No studies |
Zinc supplementation in pregnant women vs supplementation without zinc or placebo to reduce stunting Length (cm) at birth · pregnant women Nutritional interventions for preventing stunting in children (birth to 59 months) living in urban slums in… (2019) · Cochrane | no estimate extracted | 2 studies · 1337 participants | Moderate |
Nutrition education intervention for pregnant women vs standard care or no intervention, to reduce stunting Low birth weight (g) · pregnant women Nutritional interventions for preventing stunting in children (birth to 59 months) living in urban slums in… (2019) · Cochrane | MD 478.44 [423.55, 533.32] | 2 studies · 415 participants | Low |
Nutrition systems strengthening interventions targeting children vs no intervention or standard care to reduce stunting (height‐for‐age, length at 18 months) Height‐for‐age (z‐score) at 18 months · children under 5 years old Nutritional interventions for preventing stunting in children (birth to 59 months) living in urban slums in… (2019) · Cochrane | MD 0.386 [0.209, 0.562] | 1 study · 377 participants | Low |
Nutrition systems strengthening interventions targeting children vs no intervention or standard care to reduce stunting (height‐for‐age, length at 18 months) Height‐for‐age (z‐score) · children under 5 years old Nutritional interventions for preventing stunting in children (birth to 59 months) living in urban slums in… (2019) · Cochrane | no estimate extracted | 1 study · 999 participants | Very low |
Nutrition systems strengthening interventions targeting children vs no intervention or standard care to reduce stunting (height‐for‐age, length at 18 months) Length (cm) at 18 months · children under 5 years old Nutritional interventions for preventing stunting in children (birth to 59 months) living in urban slums in… (2019) · Cochrane | MD 1.068 [0.488, 1.648] | 1 study · 377 participants | Low |
Zinc supplementation in pregnant women vs supplementation without zinc or placebo to reduce stunting Length (cm) at 12 months · pregnant women Nutritional interventions for preventing stunting in children (birth to 59 months) living in urban slums in… (2019) · Cochrane | no estimate extracted | 1 study · 237 participants | Low |
Zinc supplementation in pregnant women vs supplementation without zinc or placebo to reduce stunting Low birth weight (g) · pregnant women Nutritional interventions for preventing stunting in children (birth to 59 months) living in urban slums in… (2019) · Cochrane | no estimate extracted | 2 studies · 1367 participants | Moderate |
Micronutrient or macronutrient supplementation interventions in children vs no intervention, or placebo to reduce stunting (height‐for‐age, length velocity, and length at 12 months) Height‐for‐age (z‐score) · children under 5 years old Nutritional interventions for preventing stunting in children (birth to 59 months) living in urban slums in… (2019) · Cochrane | no estimate extracted | 3 studies · 2601 participants | Low |
Micronutrient or macronutrient supplementation interventions in children vs no intervention, or placebo to reduce stunting (height‐for‐age, length velocity, and length at 12 months) Height‐for‐age (z‐score) Length gain (6 months) · children under 5 years old Nutritional interventions for preventing stunting in children (birth to 59 months) living in urban slums in… (2019) · Cochrane | no estimate extracted | 1 study · 653 participants | Low |
Micronutrient or macronutrient supplementation interventions in children vs no intervention, or placebo to reduce stunting (height‐for‐age, length velocity, and length at 12 months) Height‐for‐age (%) at 18 months, 21 months Length gain · children under 5 years old Nutritional interventions for preventing stunting in children (birth to 59 months) living in urban slums in… (2019) · Cochrane | no estimate extracted | 1 study · 324 participants | Moderate |
Micronutrient or macronutrient supplementation interventions in children vs no intervention, or placebo to reduce stunting (height‐for‐age, length velocity, and length at 12 months) Length velocity (change in cm since start of supplementation) · children under 5 years old Nutritional interventions for preventing stunting in children (birth to 59 months) living in urban slums in… (2019) · Cochrane | no estimate extracted | 1 study · 315 participants | Low |
Micronutrient or macronutrient supplementation interventions in children vs no intervention, or placebo to reduce stunting (height‐for‐age, length velocity, and length at 12 months) Length velocity (cm/month) · children under 5 years old Nutritional interventions for preventing stunting in children (birth to 59 months) living in urban slums in… (2019) · Cochrane | MD 0.22 [0.02, 0.43] | 1 study · 75 participants | Very low |
Micronutrient or macronutrient supplementation interventions in children vs no intervention, or placebo to reduce stunting (height‐for‐age, length velocity, and length at 12 months) Length (cm) at 12 months · children under 5 years old Nutritional interventions for preventing stunting in children (birth to 59 months) living in urban slums in… (2019) · Cochrane | MD 2.3 | 1 study · 100 participants | Low |
Maize flour or maize flour products fortified with folic acid alone vs no intervention Erythrocyte concentrations · health outcomes Fortification of wheat and maize flour with folic acid for population health outcomes (2019) · Cochrane | no estimate extracted | 1 study · 38 participants | Very low |
Wheat flour or wheat flour products fortified with folic acid plus other vitamins and minerals vs unfortified wheat flours or wheat flour products (not containing folic acid nor any other vitamins and minerals) Spina bifida · health: non‐randomised studies Fortification of wheat and maize flour with folic acid for population health outcomes (2019) · Cochrane | RR 0.29 [0.16, 0.56] | 8037 participants | Very low |
Wheat flour or wheat flour products fortified with folic acid plus other vitamins and minerals vs unfortified wheat flours or wheat flour products (not containing folic acid nor any other vitamins and minerals) Encephalocoele · health: non‐randomised studies Fortification of wheat and maize flour with folic acid for population health outcomes (2019) · Cochrane | RR 0.26 [0.13, 0.56] | 8037 participants | Very low |
Wheat flour or wheat flour products fortified with folic acid plus other vitamins and minerals vs unfortified wheat flours or wheat flour products (not containing folic acid nor any other vitamins and minerals) Fatal anencephaly · health: non‐randomised studies Fortification of wheat and maize flour with folic acid for population health outcomes (2019) · Cochrane | RR 0.47 [0.21, 1.07] | 8037 participants | Very low |
Wheat flour or wheat flour products fortified with folic acid plus other vitamins and minerals vs unfortified wheat flours or wheat flour products (not containing folic acid nor any other vitamins and minerals) Serum folate concentrations (nmol/L) · health: non‐randomised studies Fortification of wheat and maize flour with folic acid for population health outcomes (2019) · Cochrane | no estimate extracted | 657 participants | Very low |
Wheat flour or wheat flour products fortified with folic acid plus other vitamins and minerals vs unfortified wheat flours or wheat flour products (not containing folic acid nor any other vitamins and minerals) Anaemia · health: non‐randomised studies Fortification of wheat and maize flour with folic acid for population health outcomes (2019) · Cochrane | RR 0.87 [0.68, 1.11] | 657 participants | Very low |
Maize flour or maize flour products fortified with folic acid alone vs no intervention Serum folate concentrations · health outcomes Fortification of wheat and maize flour with folic acid for population health outcomes (2019) · Cochrane | no estimate extracted | 1 study · 38 participants | Very low |
Maize flour or maize flour products fortified with folic acid plus other vitamins and minerals vs unfortified maize flours or maize flour products (not containing folic acid nor any other vitamins and minerals) Erythrocyte folate concentrations (nmol/L) · health outcomes Fortification of wheat and maize flour with folic acid for population health outcomes (2019) · Cochrane | no estimate extracted | 1 study · 35 participants | Very low |
Maize flour or maize flour products fortified with folic acid plus other vitamins and minerals vs unfortified maize flours or maize flour products (not containing folic acid nor any other vitamins and minerals) Serum folate concentrations (nmol/L) · health outcomes Fortification of wheat and maize flour with folic acid for population health outcomes (2019) · Cochrane | no estimate extracted | 1 study · 35 participants | Very low |
Wheat flour or wheat flour products fortified with folic acid alone vs unfortified wheat flours or wheat flour products (not containing folic acid nor any other vitamins and minerals) Erythrocyte folate concentrations (nmol/L) · health outcomes Fortification of wheat and maize flour with folic acid for population health outcomes (2019) · Cochrane | no estimate extracted | 1 study · 30 participants | Very low |
Wheat flour or wheat flour products fortified with folic acid alone vs unfortified wheat flours or wheat flour products (not containing folic acid nor any other vitamins and minerals) Plasma folate concentrations (nmol/L) · health outcomes Fortification of wheat and maize flour with folic acid for population health outcomes (2019) · Cochrane | no estimate extracted | 1 study · 30 participants | Very low |
Wheat flour or wheat flour products fortified with folic acid plus other vitamins and minerals vs unfortified wheat flours or wheat flour products (not containing folic acid nor any other vitamins and minerals) Anaemia · health outcomes Fortification of wheat and maize flour with folic acid for population health outcomes (2019) · Cochrane | RR 1.07 [0.74, 1.55] | 1 study · 334 participants | Low |
Wheat flour or wheat flour products fortified with folic acid plus other vitamins and minerals vs unfortified wheat flours or wheat flour products (not containing folic acid nor any other vitamins and minerals) Haemoglobin concentrations · health outcomes Fortification of wheat and maize flour with folic acid for population health outcomes (2019) · Cochrane | no estimate extracted | 1 study · 334 participants | Low |
Wheat flour or wheat flour products fortified with folic acid plus other vitamins and minerals vs unfortified wheat flours or wheat flour products (not containing folic acid nor any other vitamins and minerals) Neural tube defects (spina bifida, encephalocoele, anencephaly‐fatal and non‐fatal) · health: non‐randomised studies Fortification of wheat and maize flour with folic acid for population health outcomes (2019) · Cochrane | RR 0.32 [0.21, 0.48] | 8037 participants | Very low |
Interventions to reduce the consumption of SSB vs no or alternative intervention: impact on SSB intake A Labelling interventions Environmental interventions to reduce the consumption of sugar‐sweetened beverages and their effects on health (2019) · Cochrane | no estimate extracted | NR | No studies |
Interventions to reduce the consumption of SSB vs no or alternative intervention: impact on SSB intake C Economic tools Environmental interventions to reduce the consumption of sugar‐sweetened beverages and their effects on health (2019) · Cochrane | no estimate extracted | NR | No studies |
Interventions to reduce the consumption of SSB vs no or alternative intervention: impact on SSB intake G Action across sectors Environmental interventions to reduce the consumption of sugar‐sweetened beverages and their effects on health (2019) · Cochrane | no estimate extracted | NR | No studies |
Economic tools vs no or alternative intervention Taxation of SSB Environmental interventions to reduce the consumption of sugar‐sweetened beverages and their effects on health (2019) · Cochrane | no estimate extracted | NR | No studies |
Lower vs higher availability (i.e. fewer versus more options) of food products Selection · Adults and children Altering the availability or proximity of food, alcohol, and tobacco products to change their selection and… (2019) · Cochrane | no estimate extracted | 3 studies · 154 participants | Low |
Lower vs higher availability (i.e. fewer versus more options) of food products Consumption · Adults and children Altering the availability or proximity of food, alcohol, and tobacco products to change their selection and… (2019) · Cochrane | no estimate extracted | 2 studies · 150 participants | Low |
Lower vs higher proximity (i.e. placed farther away versus placed nearer) of food products Selection · Adults and children Altering the availability or proximity of food, alcohol, and tobacco products to change their selection and… (2019) · Cochrane | no estimate extracted | 1 study · 41 participants | Very low |
Lower vs higher proximity (i.e. placed farther away versus placed nearer) of food products Consumption · Adults and children Altering the availability or proximity of food, alcohol, and tobacco products to change their selection and… (2019) · Cochrane | no estimate extracted | 12 studies · 1098 participants | Low |
Intervention NR Food purchased from vending machines · university students/staff and general consumers Nutritional labelling for healthier food or non‐alcoholic drink purchasing and consumption (2018) · Cochrane | no estimate extracted | 1 study · 1 participants | Very low |
Intervention NR Food purchased from a grocery store · university students/staff and general consumers Nutritional labelling for healthier food or non‐alcoholic drink purchasing and consumption (2018) · Cochrane | no estimate extracted | 1 participants | Very low |
Intervention NR Food purchased in restaurants (labels on menus) · university students/staff and general consumers Nutritional labelling for healthier food or non‐alcoholic drink purchasing and consumption (2018) · Cochrane | no estimate extracted | 3 studies · 1877 participants | Low |
Intervention NR Food consumed in laboratory settings (labels on menus or labels placed on a range of food options) · university students/staff and general consumers Nutritional labelling for healthier food or non‐alcoholic drink purchasing and consumption (2018) · Cochrane | no estimate extracted | 8 studies · 1705 participants | Low |
Intervention NR Food consumed in laboratory settings (single snack food or drink option) · university students/staff and general consumers Nutritional labelling for healthier food or non‐alcoholic drink purchasing and consumption (2018) · Cochrane | no estimate extracted | 6 studies · 732 participants | Low |