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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.

Limit to evidence status or GRADE (optional)

2,395 questions in 172 reviews · Gut

current versions
No studies 420 · 17.5%Ungraded 60 · 2.5%Very low 821 · 34.3%Low 602 · 25.1%Moderate 397 · 16.6%High 95 · 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
Antibiotics vs placebo
Failure to induce clinical remission at end of study · people with active UC
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
RR 0.88 [0.74, 1.06]7 studies · 608 participantsHigh
Antibiotics vs 5‐ASA
Failure to induce clinical response at end of study · people with active UC
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
RR 2.2 [1.17, 4.14]1 study · 46 participantsVery low
Antibiotics vs 5‐ASA
Serious adverse events · people with active UC
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
no estimate extracted1 study · 46 participantsUngraded
Antibiotics vs 5‐ASA
Withdrawals due to adverse events · people with active UC
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
no estimate extracted1 study · 46 participantsUngraded
Antibiotics vs probiotics
Failure to induce clinical remission at end of study · people with active UC
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
RR 0.47 [0.23, 0.94]1 study · 50 participantsVery low
Antibiotics vs probiotics
Failure to induce clinical response at end of study · people with active UC
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
no estimate extractedNRNo studies
Antibiotics vs probiotics
Serious adverse events · people with active UC
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
no estimate extracted1 study · 50 participantsUngraded
Antibiotics vs probiotics
Withdrawals due to adverse events · people with active UC
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
no estimate extracted1 study · 50 participantsUngraded
Antibiotics vs 5‐ASA
Failure to maintain clinical remission at end of study · people with UC in remission
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
RR 0.71 [0.47, 1.06]1 study · 40 participantsVery low
Antibiotics vs 5‐ASA
Failure to maintain clinical response at end of study · people with UC in remission
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
no estimate extractedNRNo studies
Antibiotics vs 5‐ASA
Serious adverse events · people with UC in remission
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
no estimate extracted1 study · 40 participantsUngraded
Antibiotics vs placebo
Failure to induce clinical response at end of study · people with active UC
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
RR 0.75 [0.47, 1.22]3 studies · 343 participantsLow
Antibiotics vs 5‐ASA
Withdrawals due to adverse events · people with UC in remission
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
no estimate extracted1 study · 40 participantsUngraded
Antibiotics vs no treatment
Failure to induce clinical remission at end of study · of active and inactive people with ulcerative colitis
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
RR 0.56 [0.29, 1.07]1 study · 20 participantsVery low
Antibiotics vs no treatment
Failure to induce clinical response at end of study · of active and inactive people with ulcerative colitis
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
no estimate extractedNRNo studies
Antibiotics vs no treatment
Serious adverse events · of active and inactive people with ulcerative colitis
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
no estimate extracted1 study · 20 participantsUngraded
Antibiotics vs no treatment
Withdrawals due to adverse events · of active and inactive people with ulcerative colitis
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
no estimate extracted1 study · 20 participantsUngraded
Antibiotics vs placebo
Serious adverse events · people with active UC
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
RR 1.19 [0.38, 3.71]8 studies · 691 participantsLow
Antibiotics vs placebo
Withdrawals due to adverse events · people with active UC
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
RR 2.06 [0.27, 15.72]8 studies · 691 participantsLow
Antibiotics plus probiotics vs placebo or no intervention
Failure to induce clinical remission at end of study · people with active UC
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
RR 0.68 [0.39, 1.19]2 studies · 98 participantsVery low
Antibiotics plus probiotics vs placebo or no intervention
Failure to induce clinical response at end of study · people with active UC
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
no estimate extractedNRNo studies
Antibiotics plus probiotics vs placebo or no intervention
Serious adverse events · people with active UC
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
RR 1 [0.07, 15.08]2 studies · 98 participantsVery low
Antibiotics plus probiotics vs placebo or no intervention
Withdrawals due to adverse events · people with active UC
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
RR 1 [0.07, 15.08]2 studies · 98 participantsVery low
Antibiotics vs 5‐ASA
Failure to induce clinical remission at end of study · people with active UC
Antibiotics for the induction and maintenance of remission in ulcerative colitis (2022) · Cochrane
no estimate extractedNRNo studies
Certolizumab pegol vs placebo
Failure to maintain clinical remission at week 26(1 RCT, 428 participants) · people with Crohn's disease who responded to CZP remission‐induction treatment
Certolizumab pegol for maintenance of medically induced remission in Crohn’s disease (2022) · Cochrane
RR 0.73 [0.63, 0.85]NRModerate
Certolizumab pegol vs placebo
Failure to maintain clinical response at week 26(1 RCT, 428 participants) · people with Crohn's disease who responded to CZP remission‐induction treatment
Certolizumab pegol for maintenance of medically induced remission in Crohn’s disease (2022) · Cochrane
RR 0.58 [0.48, 0.71]NRModerate
Certolizumab pegol vs placebo
Serious adverse events during remission maintenance treatment(1 RCT, 428 participants) Outcome: occurrence of infection, blood and lymphatic system disorder, immune system disorder, neoplasm, demyelinating disorders, drug‐induced systemic lupus er... · people with Crohn's disease who responded to CZP remission‐induction treatment
Certolizumab pegol for maintenance of medically induced remission in Crohn’s disease (2022) · Cochrane
RR 0.84 [0.4, 1.78]NRLow
Electromagnetic‐guided vs endoscopic‐guided postpyloric placement of nasoenteral feeding tubes
Technical success in insertion
Electromagnetic‐guided versus endoscopic‐guided postpyloric placement of nasoenteral feeding tubes (2022) · Cochrane
RR 1.09 [0.88, 1.35]4 studies · 541 participantsLow
Electromagnetic‐guided vs endoscopic‐guided postpyloric placement of nasoenteral feeding tubes
Aspiration pneumonitis
Electromagnetic‐guided versus endoscopic‐guided postpyloric placement of nasoenteral feeding tubes (2022) · Cochrane
RR 0.24 [0.03, 2.18]2 studies · 315 participantsLow
Electromagnetic‐guided vs endoscopic‐guided postpyloric placement of nasoenteral feeding tubes
Time for postpyloric placement of nasoenteral feeding tubes (minutes)
Electromagnetic‐guided versus endoscopic‐guided postpyloric placement of nasoenteral feeding tubes (2022) · Cochrane
no estimate extracted4 studies · 536 participantsLow
Electromagnetic‐guided vs endoscopic‐guided postpyloric placement of nasoenteral feeding tubes
Direct healthcare costs (USD equivalent)
Electromagnetic‐guided versus endoscopic‐guided postpyloric placement of nasoenteral feeding tubes (2022) · Cochrane
no estimate extracted3 studies · 474 participantsModerate
Electromagnetic‐guided vs endoscopic‐guided postpyloric placement of nasoenteral feeding tubes
Adverse events
Electromagnetic‐guided versus endoscopic‐guided postpyloric placement of nasoenteral feeding tubes (2022) · Cochrane
RR 0.78 [0.41, 1.49]4 studies · 536 participantsModerate
Probiotic vs placebo
Frequency of defecation, stools/week · children with chronic constipation without a physical explanation
Probiotics for treatment of chronic constipation in children (2022) · Cochrane
no estimate extracted3 studies · 280 participantsUngraded
Probiotics vs magnesium oxide
Global improvement/treatment success, as defined by the primary study · children with chronic constipation without a physical explanation
Probiotics for treatment of chronic constipation in children (2022) · Cochrane
RR 1.08 [0.74, 1.57]1 study · 36 participantsVery low
Probiotics vs magnesium oxide
Withdrawals due to adverse events · children with chronic constipation without a physical explanation
Probiotics for treatment of chronic constipation in children (2022) · Cochrane
RR 0.5 [0.05, 5.04]2 studies · 77 participantsVery low
Probiotics vs magnesium oxide
Serious adverse events · children with chronic constipation without a physical explanation
Probiotics for treatment of chronic constipation in children (2022) · Cochrane
no estimate extracted2 studies · 77 participantsUngraded
Synbiotics vs placebo
Frequency of defecation (number of stools/week at end of study) · children with chronic constipation without a physical explanation
Probiotics for treatment of chronic constipation in children (2022) · Cochrane
no estimate extractedNRNo studies
Synbiotics vs placebo
Global improvement or treatment success, as defined by primary study · children with chronic constipation without a physical explanation
Probiotics for treatment of chronic constipation in children (2022) · Cochrane
RR 2.32 [1.54, 3.47]1 study · 155 participantsLow
Synbiotics vs placebo
Withdrawals due to adverse events · children with chronic constipation without a physical explanation
Probiotics for treatment of chronic constipation in children (2022) · Cochrane
no estimate extracted1 study · 155 participantsUngraded
Synbiotics vs placebo
Serious adverse events · children with chronic constipation without a physical explanation
Probiotics for treatment of chronic constipation in children (2022) · Cochrane
no estimate extracted1 study · 155 participantsUngraded
Synbiotics and paraffin vs paraffin
Frequency of defecation (number of stools/week) · children with chronic constipation without a physical explanation
Probiotics for treatment of chronic constipation in children (2022) · Cochrane
no estimate extracted1 study · 66 participantsVery low
Synbiotics and paraffin vs paraffin
Global improvement or treatment success, as defined by primary studies · children with chronic constipation without a physical explanation
Probiotics for treatment of chronic constipation in children (2022) · Cochrane
RR 0.91 [0.71, 1.17]1 study · 66 participantsVery low
Synbiotics and paraffin vs paraffin
Withdrawals due to adverse events · children with chronic constipation without a physical explanation
Probiotics for treatment of chronic constipation in children (2022) · Cochrane
no estimate extracted1 study · 66 participantsUngraded
Probiotic vs placebo
Global improvement/treatment success as defined by primary study · children with chronic constipation without a physical explanation
Probiotics for treatment of chronic constipation in children (2022) · Cochrane
RR 1.294 studies · 313 participantsLow
Synbiotics and paraffin vs paraffin
Serious adverse events · children with chronic constipation without a physical explanation
Probiotics for treatment of chronic constipation in children (2022) · Cochrane
no estimate extracted1 study · 66 participantsUngraded
Synbiotics vs paraffin
Frequency of defecation (number of stools/week) · children with chronic constipation without a physical explanation
Probiotics for treatment of chronic constipation in children (2022) · Cochrane
no estimate extracted1 study · 60 participantsVery low
Synbiotics vs paraffin
Global improvement or treatment success, as defined by primary studies · children with chronic constipation without a physical explanation
Probiotics for treatment of chronic constipation in children (2022) · Cochrane
RR 0.86 [0.65, 1.13]1 study · 60 participantsVery low
Synbiotics vs paraffin
Withdrawals due to adverse events · children with chronic constipation without a physical explanation
Probiotics for treatment of chronic constipation in children (2022) · Cochrane
no estimate extracted1 study · 60 participantsUngraded
Synbiotics vs paraffin
Serious adverse events · children with chronic constipation without a physical explanation
Probiotics for treatment of chronic constipation in children (2022) · Cochrane
no estimate extracted1 study · 60 participantsUngraded
Probiotic vs placebo
Withdrawals due to adverse events · children with chronic constipation without a physical explanation
Probiotics for treatment of chronic constipation in children (2022) · Cochrane
RR 0.64 [0.21, 1.95]5 studies · 357 participantsLow