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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.

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Intervention or exposure

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Review versions

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.

Question	Effect	Evidence	Status / GRADE
Oral 5‐aminosalicylic acid vs placebo Failure to adhere to study medication · people with quiescent UC Oral 5‐aminosalicylic acid for maintenance of remission in ulcerative colitis (2020) · Cochrane	no estimate extracted	NR	No studies
Oral 5‐aminosalicylic acid vs comparator 5‐aminosalicylic acid formulation Failure to adhere to study medication regimen · people with quiescent UC Oral 5‐aminosalicylic acid for maintenance of remission in ulcerative colitis (2020) · Cochrane	no estimate extracted	NR	No studies
Oral 5‐aminosalicylic acid vs comparator 5‐aminosalicylic acid formulation Adverse event · people with quiescent UC Oral 5‐aminosalicylic acid for maintenance of remission in ulcerative colitis (2020) · Cochrane	RR 0.94 [0.83, 1.07]	4 studies · 357 participants	Low
Oral 5‐aminosalicylic acid vs comparator 5‐aminosalicylic acid formulation Serious adverse events · people with quiescent UC Oral 5‐aminosalicylic acid for maintenance of remission in ulcerative colitis (2020) · Cochrane	RR 0.56 [0.14, 2.22]	1 study · 95 participants	Low
Oral 5‐aminosalicylic acid vs comparator 5‐aminosalicylic acid formulation Withdrawal due to adverse events · people with quiescent UC Oral 5‐aminosalicylic acid for maintenance of remission in ulcerative colitis (2020) · Cochrane	RR 1.25	5 studies · 457 participants	Very low
Oral 5‐aminosalicylic acid vs comparator 5‐aminosalicylic acid formulation Exclusion/withdrawal after entry · people with quiescent UC Oral 5‐aminosalicylic acid for maintenance of remission in ulcerative colitis (2020) · Cochrane	RR 1.23 [0.9, 1.7]	5 studies · 457 participants	Moderate
Oral 5‐aminosalicylic acid vs placebo Adverse events · people with quiescent UC Oral 5‐aminosalicylic acid for maintenance of remission in ulcerative colitis (2020) · Cochrane	RR 0.93 [0.73, 1.18]	5 studies · 1132 participants	Moderate
Oral 5‐aminosalicylic acid vs placebo Serious adverse events · people with quiescent UC Oral 5‐aminosalicylic acid for maintenance of remission in ulcerative colitis (2020) · Cochrane	RR 0.6 [0.19, 1.84]	3 studies · 826 participants	Low
Oral 5‐aminosalicylic acid vs placebo Withdrawal due to adverse event · people with quiescent UC Oral 5‐aminosalicylic acid for maintenance of remission in ulcerative colitis (2020) · Cochrane	RR 1.22 [0.76, 1.95]	7 studies · 1454 participants	Moderate
Oral 5‐aminosalicylic acid vs placebo Exclusion/withdrawal after entry · people with quiescent UC Oral 5‐aminosalicylic acid for maintenance of remission in ulcerative colitis (2020) · Cochrane	RR 1.13 [0.88, 1.44]	5 studies · 1074 participants	Moderate
Oral 5‐aminosalicylic acid vs sulfasalazine Failure to maintain clinical or endoscopic remission · people with quiescent ulcerative colitis Oral 5‐aminosalicylic acid for maintenance of remission in ulcerative colitis (2020) · Cochrane	RR 1.14 [1.03, 1.27]	12 studies · 1655 participants	High
Oral 5‐aminosalicylic acid vs sulfasalazine Failure to adhere to study medication · people with quiescent ulcerative colitis Oral 5‐aminosalicylic acid for maintenance of remission in ulcerative colitis (2020) · Cochrane	no estimate extracted	NR	No studies
Oral 5‐aminosalicylic acid vs sulfasalazine Adverse event · people with quiescent ulcerative colitis Oral 5‐aminosalicylic acid for maintenance of remission in ulcerative colitis (2020) · Cochrane	RR 1.07 [0.82, 1.4]	7 studies · 1138 participants	Moderate
Probiotics vs placebo Clinical remission · people with active ulcerative colitis Probiotics for induction of remission in ulcerative colitis (2020) · Cochrane	RR 1.73 [1.19, 2.54]	9 studies · 594 participants	Low
Probiotics vs 5‐aminosalicylic acid (5‐ASA) (mesalazine) Disease improvement · people with active ulcerative colitis Probiotics for induction of remission in ulcerative colitis (2020) · Cochrane	no estimate extracted	NR	No studies
Probiotics plus 5‐aminosalicylic acid (5‐ASA) (mesalazine) vs 5‐aminosalicylic acid (5‐ASA) (mesalazine) Remission · people with active ulcerative colitis Probiotics for induction of remission in ulcerative colitis (2020) · Cochrane	RR 1.22 [1.01, 1.47]	1 study · 84 participants	Low
Probiotics plus 5‐aminosalicylic acid (5‐ASA) (mesalazine) vs 5‐aminosalicylic acid (5‐ASA) (mesalazine) Disease improvement · people with active ulcerative colitis Probiotics for induction of remission in ulcerative colitis (2020) · Cochrane	no estimate extracted	NR	No studies
Probiotics plus 5‐aminosalicylic acid (5‐ASA) (mesalazine) vs 5‐aminosalicylic acid (5‐ASA) (mesalazine) Minor adverse events · people with active ulcerative colitis Probiotics for induction of remission in ulcerative colitis (2020) · Cochrane	no estimate extracted	NR	No studies
Probiotics plus 5‐aminosalicylic acid (5‐ASA) (mesalazine) vs 5‐aminosalicylic acid (5‐ASA) (mesalazine) Serious adverse events · people with active ulcerative colitis Probiotics for induction of remission in ulcerative colitis (2020) · Cochrane	no estimate extracted	NR	No studies
Probiotics plus 5‐aminosalicylic acid (5‐ASA) (mesalazine) vs 5‐aminosalicylic acid (5‐ASA) (mesalazine) Withdrawal due to adverse events · people with active ulcerative colitis Probiotics for induction of remission in ulcerative colitis (2020) · Cochrane	no estimate extracted	NR	No studies
Probiotics vs placebo Disease improvement (based on clinical scores) · people with active ulcerative colitis Probiotics for induction of remission in ulcerative colitis (2020) · Cochrane	RR 2.29 [1.13, 4.63]	2 studies · 54 participants	Low
Probiotics vs placebo Minor adverse events · people with active ulcerative colitis Probiotics for induction of remission in ulcerative colitis (2020) · Cochrane	RR 1.04 [0.42, 2.59]	7 studies · 520 participants	Very low
Probiotics vs placebo Serious adverse events · people with active ulcerative colitis Probiotics for induction of remission in ulcerative colitis (2020) · Cochrane	RR 0.09 [0.01, 1.66]	7 studies · 526 participants	Very low
Probiotics vs placebo Withdrawal due to adverse events · people with active ulcerative colitis Probiotics for induction of remission in ulcerative colitis (2020) · Cochrane	RR 0.85 [0.42, 1.72]	4 studies · 401 participants	Low
Probiotics vs 5‐aminosalicylic acid (5‐ASA) (mesalazine) Clinical remission · people with active ulcerative colitis Probiotics for induction of remission in ulcerative colitis (2020) · Cochrane	RR 0.92 [0.73, 1.16]	1 study · 116 participants	Low
Probiotics vs 5‐aminosalicylic acid (5‐ASA) (mesalazine) Minor adverse events · people with active ulcerative colitis Probiotics for induction of remission in ulcerative colitis (2020) · Cochrane	RR 1	2 studies · 192 participants	Very low
Probiotics vs 5‐aminosalicylic acid (5‐ASA) (mesalazine) Serious adverse events · people with active ulcerative colitis Probiotics for induction of remission in ulcerative colitis (2020) · Cochrane	RR 0.21 [0.01, 4.22]	1 study · 116 participants	Very low
Probiotics vs 5‐aminosalicylic acid (5‐ASA) (mesalazine) Withdrawal due to adverse events · people with active ulcerative colitis Probiotics for induction of remission in ulcerative colitis (2020) · Cochrane	RR 0.21 [0.01, 4.22]	1 study · 116 participants	Very low
H. pylori eradication therapy vs control Incidence of gastric cancer ‐ modified ITT analysisHistological examination · healthy asymptomatic H. pylori‐infected individuals Helicobacter pylori eradication for the prevention of gastric neoplasia (2020) · Cochrane	RR 0.54 [0.4, 0.72]	7 studies · 8323 participants	Moderate
H. pylori eradication therapy vs control Death from gastric cancer ‐ modified ITT analysis · healthy asymptomatic H. pylori‐infected individuals Helicobacter pylori eradication for the prevention of gastric neoplasia (2020) · Cochrane	RR 0.61 [0.4, 0.92]	4 studies · 6301 participants	Moderate
H. pylori eradication therapy vs control Death from all causes ‐ modified ITT analysis · healthy asymptomatic H. pylori‐infected individuals Helicobacter pylori eradication for the prevention of gastric neoplasia (2020) · Cochrane	RR 0.97 [0.85, 1.12]	5 studies · 7079 participants	Moderate
H. pylori eradication therapy vs control Incidence of oesophageal squamous cell carcinoma ‐ modified ITT analysis · healthy asymptomatic H. pylori‐infected individuals Helicobacter pylori eradication for the prevention of gastric neoplasia (2020) · Cochrane	RR 1.22 [0.59, 2.54]	2 studies · 3888 participants	Moderate
H. pylori eradication therapy vs control Adverse events · healthy asymptomatic H. pylori‐infected individuals Helicobacter pylori eradication for the prevention of gastric neoplasia (2020) · Cochrane	no estimate extracted	0 studies · 0 participants	Ungraded
Probiotics vs placebo Induction of remission · induction of remission in Crohn's disease Probiotics for induction of remission in Crohn's disease (2020) · Cochrane	RR 1.06 [0.65, 1.71]	2 studies · 46 participants	Very low
Probiotics vs placebo Adverse events leading to withdrawal · induction of remission in Crohn's disease Probiotics for induction of remission in Crohn's disease (2020) · Cochrane	RR 2.55 [0.11, 58.6]	2 studies · 35 participants	Very low
Diazepam and glucagon vs placebo Disimpaction · management of impacted food bolus in the oesophagus Conservative management of oesophageal soft food bolus impaction (2020) · Cochrane	RR 1.19 [0.51, 2.75]	1 study · 43 participants	Low
Probiotics vs placebo Clinical relapse (12 to 52 weeks) · people with ulcerative colitis in remission Probiotics for maintenance of remission in ulcerative colitis (2020) · Cochrane	RR 0.87 [0.63, 1.18]	4 studies · 361 participants	Very low
Probiotics vs 5‐aminosalicylic acid (5‐ASA) (mesalazine) Withdrawal due to adverse events (52 weeks) · people with ulcerative colitis in remission Probiotics for maintenance of remission in ulcerative colitis (2020) · Cochrane	RR 1.02 [0.46, 2.25]	1 study · 222 participants	Very low
Probiotics vs 5‐aminosalicylic acid (5‐ASA) (mesalazine) Need for additional therapy · people with ulcerative colitis in remission Probiotics for maintenance of remission in ulcerative colitis (2020) · Cochrane	no estimate extracted	NR	No studies
Probiotics vs 5‐aminosalicylic acid (5‐ASA) (mesalazine) Health‐related quality of life (52 weeks) · people with ulcerative colitis in remission Probiotics for maintenance of remission in ulcerative colitis (2020) · Cochrane	no estimate extracted	1 study · 222 participants	Low
Probiotic + 5‐aminosalicylic acid (5‐ASA) (mesalazine) vs 5‐ASA (mesalazine) Clinical relapse (12 to 52 weeks) · people with ulcerative colitis in remission Probiotics for maintenance of remission in ulcerative colitis (2020) · Cochrane	RR 1.11 [0.66, 1.87]	2 studies · 242 participants	Very low
Probiotic + 5‐aminosalicylic acid (5‐ASA) (mesalazine) vs 5‐ASA (mesalazine) Maintenance of clinical remission (24 to 52 weeks) · people with ulcerative colitis in remission Probiotics for maintenance of remission in ulcerative colitis (2020) · Cochrane	RR 1.05 [0.89, 1.24]	1 study · 122 participants	Low
Probiotic + 5‐aminosalicylic acid (5‐ASA) (mesalazine) vs 5‐ASA (mesalazine) Serious adverse events · people with ulcerative colitis in remission Probiotics for maintenance of remission in ulcerative colitis (2020) · Cochrane	no estimate extracted	NR	No studies
Probiotic + 5‐aminosalicylic acid (5‐ASA) (mesalazine) vs 5‐ASA (mesalazine) Withdrawal due to adverse events (12 to 52 weeks) · people with ulcerative colitis in remission Probiotics for maintenance of remission in ulcerative colitis (2020) · Cochrane	RR 5.29 [0.26, 107.63]	2 studies · 127 participants	Very low
Probiotic + 5‐aminosalicylic acid (5‐ASA) (mesalazine) vs 5‐ASA (mesalazine) Need for additional therapy · people with ulcerative colitis in remission Probiotics for maintenance of remission in ulcerative colitis (2020) · Cochrane	no estimate extracted	NR	No studies
Probiotic + 5‐aminosalicylic acid (5‐ASA) (mesalazine) vs 5‐ASA (mesalazine) Health‐related quality of life · people with ulcerative colitis in remission Probiotics for maintenance of remission in ulcerative colitis (2020) · Cochrane	no estimate extracted	NR	No studies
Probiotics vs placebo Maintenance of clinical remission (52 weeks) · people with ulcerative colitis in remission Probiotics for maintenance of remission in ulcerative colitis (2020) · Cochrane	RR 1.16 [0.98, 1.37]	2 studies · 141 participants	Very low
Probiotics vs placebo Serious adverse events (48 to 52 weeks) · people with ulcerative colitis in remission Probiotics for maintenance of remission in ulcerative colitis (2020) · Cochrane	no estimate extracted	4 studies · 351 participants	Ungraded
Probiotics vs placebo Withdrawal due to adverse events · people with ulcerative colitis in remission Probiotics for maintenance of remission in ulcerative colitis (2020) · Cochrane	no estimate extracted	2 studies · 113 participants	Ungraded
Probiotics vs placebo Need for additional therapy · people with ulcerative colitis in remission Probiotics for maintenance of remission in ulcerative colitis (2020) · Cochrane	no estimate extracted	NR	No studies