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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. Every word you type has to appear somewhere in the question, and the closest matches are ranked first.

Limit to evidence status or GRADE (optional)

75,239 questions in 5,342 reviews

current versions
No studies 15,213 · 20.2%Ungraded 10,323 · 13.7%Very low 17,528 · 23.3%Low 17,951 · 23.9%Moderate 11,190 · 14.9%High 3,034 · 4%

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.

QuestionEffectEvidenceStatus / GRADE
Summary of findings table ‐ Metformin vs megestrol
Regression of endometrial hyperplasia (with or without atypia) to proliferative, secretory, or atrophic endometrium · endometrial hyperplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
OR 4.89 [1.56, 15.32]2 studies · 83 participantsVery low
Summary of findings table ‐ Metformin + megestrol vs megestrol
Progression of endometrial hyperplasia to endometrial cancer · endometrial hyerplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
OR 7.96 [0.16, 402.02]3 studies · 156 participantsVery low
Summary of findings table ‐ Metformin + megestrol vs megestrol
Hysterectomy rate · endometrial hyerplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
OR 7.39 [0.15, 372.38]2 studies · 72 participantsVery low
Summary of findings table ‐ Metformin + megestrol vs megestrol
Abnormal uterine bleeding ‐ not measured · endometrial hyerplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
no estimate extractedNRNo studies
Summary of findings table ‐ Metformin + megestrol vs megestrol
Health‐related quality of life (HRQoL) ‐ not measured · endometrial hyerplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
no estimate extractedNRNo studies
Summary of findings table ‐ Metformin + megestrol vs megestrol
Adverse effects during treatment · endometrial hyerplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
no estimate extracted1 study · 8 participantsVery low
Summary of findings table ‐ Metformin + levonorgestrel (intrauterine system) vs levonorgestrel intrauterine system
Regression of endometrial hyperplasia (with or without atypia) to proliferative, secretory, or atrophic endometrium · endometrial hyperplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
OR 3.42 [0.13, 88.4]1 study · 46 participantsVery low
Summary of findings table ‐ Metformin + levonorgestrel (intrauterine system) vs levonorgestrel intrauterine system
Recurrence of endometrial hyperplasia ‐ not reported · endometrial hyperplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
no estimate extractedNRNo studies
Summary of findings table ‐ Metformin + levonorgestrel (intrauterine system) vs levonorgestrel intrauterine system
Progression of endometrial hyperplasia to endometrial cancer · endometrial hyperplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
no estimate extracted1 study · 1 participantsVery low
Summary of findings table ‐ Metformin + levonorgestrel (intrauterine system) vs levonorgestrel intrauterine system
Hysterectomy rate · endometrial hyperplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
OR 0.12 [0.01, 1.95]1 study · 46 participantsVery low
Summary of findings table ‐ Metformin + levonorgestrel (intrauterine system) vs levonorgestrel intrauterine system
Abnormal uterine bleeding · endometrial hyperplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
OR 0.61 [0.16, 2.27]1 study · 49 participantsVery low
Summary of findings table ‐ Metformin vs megestrol
Recurrence of endometrial hyperplasia ‐ not reported · endometrial hyperplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Summary of findings table ‐ Metformin + levonorgestrel (intrauterine system) vs levonorgestrel intrauterine system
Adverse effects during treatment ‐ all effects · endometrial hyperplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
OR 4 [1.15, 13.9]1 study · 51 participantsVery low
Summary of findings table ‐ Metformin + levonorgestrel (intrauterine system) vs levonorgestrel intrauterine system
Adverse effects during treatment ‐ nausea · endometrial hyperplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
OR 5.11 [1.21, 21.68]1 study · 51 participantsVery low
Summary of findings table ‐ Metformin + levonorgestrel (intrauterine system) vs levonorgestrel intrauterine system
Adverse effects during treatment ‐ heaviness in lower abdomen · endometrial hyperplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
OR 1.38 [0.32, 5.85]1 study · 51 participantsVery low
Summary of findings table ‐ Metformin + levonorgestrel (intrauterine system) vs levonorgestrel intrauterine system
Adverse effects during treatment ‐ pain in abdomen · endometrial hyperplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
OR 0.83 [0.22, 3.18]1 study · 51 participantsVery low
Summary of findings table ‐ Metformin vs megestrol
Progression of endometrial hyperplasia to endometrial cancer · endometrial hyperplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
no estimate extracted2 studies · 2 participantsVery low
Summary of findings table ‐ Metformin vs megestrol
Hysterectomy rate · endometrial hyperplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
OR 0.91 [0.05, 15.52]2 studies · 85 participantsVery low
Summary of findings table ‐ Metformin vs megestrol
Abnormal uterine bleeding · endometrial hyperplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
OR 0.91 [0.05, 15.52]1 study · 44 participantsVery low
Summary of findings table ‐ Metformin vs megestrol
Health‐related quality of life (HRQoL) ‐ not measured · endometrial hyperplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
no estimate extractedNRNo studies
Summary of findings table ‐ Metformin vs megestrol
Adverse effects during treatment ‐ not reported · endometrial hyperplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
no estimate extractedNRNo studies
Summary of findings table ‐ Metformin + megestrol vs megestrol
Regression of endometrial hyperplasia (with or without atypia) to proliferative, secretory, or atrophic endometrium · endometrial hyerplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
OR 3.27 [1.65, 6.51]4 studies · 258 participantsLow
Summary of findings table ‐ Metformin + megestrol vs megestrol
Recurrence of endometrial hyperplasia · endometrial hyerplasia
Metformin for endometrial hyperplasia (2024) · Cochrane
no estimate extracted1 study · 8 participantsVery low
Summary of findings table ‐ Probiotics vs placebo
Proven sepsis (positive bacterial culture, local or systemic) · neonates born from 35 weeks of gestation who have underdone gastrointestinal surgery
Probiotics for the postoperative management of term neonates after gastrointestinal surgery (2024) · Cochrane
OR 0.64 [0.16, 2.55]1 study · 61 participantsLow
Summary of findings table ‐ Probiotics vs placebo
All‐cause neonatal mortality (28 days) · neonates born from 35 weeks of gestation who have underdone gastrointestinal surgery
Probiotics for the postoperative management of term neonates after gastrointestinal surgery (2024) · Cochrane
no estimate extracted0 studies · 0 participantsUngraded
Summary of findings table ‐ Probiotics vs placebo
Time to full enteral feeds in daysScale from: 0 to 100 · neonates born from 35 weeks of gestation who have underdone gastrointestinal surgery
Probiotics for the postoperative management of term neonates after gastrointestinal surgery (2024) · Cochrane
no estimate extracted1 study · 61 participantsLow
Summary of findings table ‐ Probiotics vs placebo
All‐cause mortality prior to discharge · neonates born from 35 weeks of gestation who have underdone gastrointestinal surgery
Probiotics for the postoperative management of term neonates after gastrointestinal surgery (2024) · Cochrane
no estimate extracted1 study · 61 participantsUngraded
Summary of findings table ‐ Probiotics vs placebo
Non‐pathogenic intestinal microflora (relative abundance) · neonates born from 35 weeks of gestation who have underdone gastrointestinal surgery
Probiotics for the postoperative management of term neonates after gastrointestinal surgery (2024) · Cochrane
no estimate extracted1 study · 39 participantsLow
Intervention NR
Body weight change (kg) · participants living with overweight or obesity
Calcium supplementation for people with overweight or obesity (2024) · Cochrane
no estimate extracted17 studies · 1317 participantsLow
Intervention NR
Health‐related quality of life · participants living with overweight or obesity
Calcium supplementation for people with overweight or obesity (2024) · Cochrane
no estimate extractedNRNo studies
Intervention NR
Adverse events · participants living with overweight or obesity
Calcium supplementation for people with overweight or obesity (2024) · Cochrane
no estimate extracted5 studies · 854 participantsLow
Intervention NR
All‐cause mortality · participants living with overweight or obesity
Calcium supplementation for people with overweight or obesity (2024) · Cochrane
no estimate extractedNRNo studies
Intervention NR
Morbidity · participants living with overweight or obesity
Calcium supplementation for people with overweight or obesity (2024) · Cochrane
no estimate extractedNRNo studies
Intervention NR
Anthropometric measures other than body weight a) BMI b) Waist circumference c) Fat mass · participants living with overweight or obesity
Calcium supplementation for people with overweight or obesity (2024) · Cochrane
no estimate extracted9 studies · 731 participantsModerate
Structured risk assessment vs standard professional care
Scientific behaviour: aggression – clinically important change in aggressive/violent behaviour, as defined by the individual studies · aggressive behaviour in schizophrenia
Risk assessment for aggressive behaviour in schizophrenia (2024) · Cochrane
RR 0.59 [0.41, 0.85]1 study · 1852 participantsModerate
Structured risk assessment vs standard professional care
Use of coercive measure: use of seclusion room (time, days) · aggressive behaviour in schizophrenia
Risk assessment for aggressive behaviour in schizophrenia (2024) · Cochrane
RR 0.92 [0.27, 3.07]1 study · 20 participantsLow
Structured risk assessment vs standard professional care
Use of coercive measure: use of seclusion room (participants) · aggressive behaviour in schizophrenia
Risk assessment for aggressive behaviour in schizophrenia (2024) · Cochrane
RR 1.83 [0.39, 8.7]1 study · 20 participantsLow
Structured risk assessment vs standard professional care
Use of coercive measure: use of seclusion room (incidents) · aggressive behaviour in schizophrenia
Risk assessment for aggressive behaviour in schizophrenia (2024) · Cochrane
RR 1.63 [0.49, 5.47]1 study · 20 participantsLow
Structured risk assessment vs standard professional care
Adverse effects (escape) · aggressive behaviour in schizophrenia
Risk assessment for aggressive behaviour in schizophrenia (2024) · Cochrane
RR 0.2 [0.01, 4.11]1 study · 200 participantsVery low
Structured risk assessment vs standard professional care
Adverse effects (fall down) · aggressive behaviour in schizophrenia
Risk assessment for aggressive behaviour in schizophrenia (2024) · Cochrane
RR 0.33 [0.04, 3.15]1 study · 200 participantsVery low
Structured risk assessment vs standard professional care
Adverse effects (choking) · aggressive behaviour in schizophrenia
Risk assessment for aggressive behaviour in schizophrenia (2024) · Cochrane
RR 0.2 [0.01, 4.11]1 study · 200 participantsVery low
Mindfulness‐enhanced parent training vs no‐treatment, waitlist, or attentional control
Child emotional and behavioural adjustment; postintervention · parents of children between the ages of 0 and 18 years
Mindfulness‐enhanced parenting programmes for improving the psychosocial outcomes of children (0 to 18… (2024) · Cochrane
no estimate extracted3 studies · 270 participantsVery low
Mindfulness‐enhanced parent training vs parent training
Parenting skills; postintervention · parents of children between the ages of 0 and 18 years
Mindfulness‐enhanced parenting programmes for improving the psychosocial outcomes of children (0 to 18… (2024) · Cochrane
no estimate extracted3 studies · 319 participantsVery low
Mindfulness‐enhanced parent training vs parent training
Parental depression or anxiety; postintervention · parents of children between the ages of 0 and 18 years
Mindfulness‐enhanced parenting programmes for improving the psychosocial outcomes of children (0 to 18… (2024) · Cochrane
no estimate extracted1 study · 45 participantsVery low
Mindfulness‐enhanced parent training vs parent training
Parenting stress; postintervention · parents of children between the ages of 0 and 18 years
Mindfulness‐enhanced parenting programmes for improving the psychosocial outcomes of children (0 to 18… (2024) · Cochrane
no estimate extracted3 studies · 150 participantsLow
Mindfulness‐enhanced parent training vs parent training
Parent mindfulness; postintervention · parents of children between the ages of 0 and 18 years
Mindfulness‐enhanced parenting programmes for improving the psychosocial outcomes of children (0 to 18… (2024) · Cochrane
no estimate extracted4 studies · 412 participantsVery low
Mindfulness‐enhanced parent training vs parent training
Measures of self‐compassion · parents of children between the ages of 0 and 18 years
Mindfulness‐enhanced parenting programmes for improving the psychosocial outcomes of children (0 to 18… (2024) · Cochrane
no estimate extractedNRNo studies
Mindfulness‐enhanced parent training vs no‐treatment, waitlist, or attentional control
Adverse effects · parents of children between the ages of 0 and 18 years
Mindfulness‐enhanced parenting programmes for improving the psychosocial outcomes of children (0 to 18… (2024) · Cochrane
no estimate extractedNRNo studies
Mindfulness‐enhanced parent training vs no‐treatment, waitlist, or attentional control
Parenting skills; postintervention · parents of children between the ages of 0 and 18 years
Mindfulness‐enhanced parenting programmes for improving the psychosocial outcomes of children (0 to 18… (2024) · Cochrane
no estimate extracted3 studies · 587 participantsVery low
Mindfulness‐enhanced parent training vs no‐treatment, waitlist, or attentional control
Parental depression or anxiety; postintervention · parents of children between the ages of 0 and 18 years
Mindfulness‐enhanced parenting programmes for improving the psychosocial outcomes of children (0 to 18… (2024) · Cochrane
no estimate extracted1 study · 75 participantsVery low