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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.
2,395 questions in 172 reviews · Gut
current versionsNo 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 |
|---|---|---|---|
Probiotic 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 extracted | 4 studies · 198 participants | Ungraded |
Probiotics and osmotic laxative vs osmotic laxative 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 extracted | 3 studies · 268 participants | Low |
Probiotics and osmotic laxative vs osmotic laxative 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 0.95 [0.79, 1.15] | 2 studies · 139 participants | Low |
Probiotics and osmotic laxative vs osmotic laxative Withdrawal due to adverse events · children with chronic constipation without a physical explanation Probiotics for treatment of chronic constipation in children (2022) · Cochrane | RR 2.86 [0.12, 68.35] | 3 studies · 268 participants | Very low |
Probiotics and osmotic laxative vs osmotic laxative Serious adverse events · children with chronic constipation without a physical explanation Probiotics for treatment of chronic constipation in children (2022) · Cochrane | no estimate extracted | 4 studies · 308 participants | Ungraded |
Probiotics vs magnesium oxide 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 extracted | 1 study · 36 participants | Very low |
Antidepressant vs placebo Treatment success · Children and adolescents with functional abdominal pain disorder Antidepressants for functional abdominal pain disorders in children and adolescents (2021) · Cochrane | RR 1.17 [0.87, 1.56] | 2 studies · 205 participants | Low |
Antidepressant vs placebo Withdrawals due to adverse events · Children and adolescents with functional abdominal pain disorder Antidepressants for functional abdominal pain disorders in children and adolescents (2021) · Cochrane | RR 3.17 [0.65, 15.33] | 3 studies · 238 participants | Low |
Drain use vs no drain use following pancreatic surgery Mortality · people undergoing elective pancreatic resections Prophylactic abdominal drainage for pancreatic surgery (2021) · Cochrane | RR 0.78 [0.31, 1.99] | 4 studies · 1055 participants | Low |
Active drain vs passive drain following pancreatic surgery Intra‐abdominal infection · people undergoing elective pancreatic resections Prophylactic abdominal drainage for pancreatic surgery (2021) · Cochrane | RR 0.87 [0.21, 3.66] | 2 studies · 321 participants | Very low |
Active drain vs passive drain following pancreatic surgery Wound infection · people undergoing elective pancreatic resections Prophylactic abdominal drainage for pancreatic surgery (2021) · Cochrane | RR 0.92 [0.44, 1.9] | 2 studies · 321 participants | Very low |
Active drain vs passive drain following pancreatic surgery Drain‐related complications · people undergoing elective pancreatic resections Prophylactic abdominal drainage for pancreatic surgery (2021) · Cochrane | no estimate extracted | 1 study · 223 participants | Very low |
Active drain vs passive drain following pancreatic surgery Morbidity · people undergoing elective pancreatic resections Prophylactic abdominal drainage for pancreatic surgery (2021) · Cochrane | RR 0.97 [0.53, 1.77] | 2 studies · 382 participants | Very low |
Active drain vs passive drain following pancreatic surgery Length of hospital stay · people undergoing elective pancreatic resections Prophylactic abdominal drainage for pancreatic surgery (2021) · Cochrane | no estimate extracted | 2 studies · 321 participants | Very low |
Early vs late drain removal following pancreatic surgery Mortality · people undergoing elective pancreatic resections Prophylactic abdominal drainage for pancreatic surgery (2021) · Cochrane | RR 0.99 [0.06, 15.45] | 3 studies · 399 participants | Very low |
Early vs late drain removal following pancreatic surgery Mortality · people undergoing elective pancreatic resections Prophylactic abdominal drainage for pancreatic surgery (2021) · Cochrane | no estimate extracted | NR | No studies |
Early vs late drain removal following pancreatic surgery Intra‐abdominal infection · people undergoing elective pancreatic resections Prophylactic abdominal drainage for pancreatic surgery (2021) · Cochrane | RR 0.44 [0.22, 0.89] | 2 studies · 285 participants | Very low |
Early vs late drain removal following pancreatic surgery Wound infection · people undergoing elective pancreatic resections Prophylactic abdominal drainage for pancreatic surgery (2021) · Cochrane | RR 1.32 [0.45, 3.85] | 2 studies · 285 participants | Very low |
Early vs late drain removal following pancreatic surgery Drain‐related complications · people undergoing elective pancreatic resections Prophylactic abdominal drainage for pancreatic surgery (2021) · Cochrane | no estimate extracted | NR | No studies |
Drain use vs no drain use following pancreatic surgery Mortality · people undergoing elective pancreatic resections Prophylactic abdominal drainage for pancreatic surgery (2021) · Cochrane | RR 0.23 [0.06, 0.9] | 2 studies · 478 participants | Low |
Early vs late drain removal following pancreatic surgery Morbidity · people undergoing elective pancreatic resections Prophylactic abdominal drainage for pancreatic surgery (2021) · Cochrane | RR 0.49 [0.3, 0.81] | 2 studies · 258 participants | Very low |
Early vs late drain removal following pancreatic surgery Length of hospital stay · people undergoing elective pancreatic resections Prophylactic abdominal drainage for pancreatic surgery (2021) · Cochrane | no estimate extracted | 3 studies · 399 participants | Very low |
Drain use vs no drain use following pancreatic surgery Intra‐abdominal infection · people undergoing elective pancreatic resections Prophylactic abdominal drainage for pancreatic surgery (2021) · Cochrane | RR 0.97 [0.52, 1.8] | 4 studies · 1055 participants | Very low |
Drain use vs no drain use following pancreatic surgery Wound infection · people undergoing elective pancreatic resections Prophylactic abdominal drainage for pancreatic surgery (2021) · Cochrane | RR 0.98 [0.68, 1.41] | 4 studies · 1055 participants | Low |
Drain use vs no drain use following pancreatic surgery Drain‐related complications · people undergoing elective pancreatic resections Prophylactic abdominal drainage for pancreatic surgery (2021) · Cochrane | no estimate extracted | 1 study · 179 participants | Low |
Drain use vs no drain use following pancreatic surgery Morbidity · people undergoing elective pancreatic resections Prophylactic abdominal drainage for pancreatic surgery (2021) · Cochrane | RR 1.03 [0.94, 1.13] | 4 studies · 1055 participants | Moderate |
Drain use vs no drain use following pancreatic surgery Length of hospital stay · people undergoing elective pancreatic resections Prophylactic abdominal drainage for pancreatic surgery (2021) · Cochrane | no estimate extracted | 3 studies · 876 participants | Low |
Active drain vs passive drain following pancreatic surgery Mortality · people undergoing elective pancreatic resections Prophylactic abdominal drainage for pancreatic surgery (2021) · Cochrane | RR 1.23 [0.3, 5.06] | 2 studies · 382 participants | Very low |
Active drain vs passive drain following pancreatic surgery Mortality · people undergoing elective pancreatic resections Prophylactic abdominal drainage for pancreatic surgery (2021) · Cochrane | no estimate extracted | NR | No studies |
Extended vs standard lymph node resection Overall survival (1‐year · people with pancreatic and periampullary adenocarcinoma Extended lymph node resection versus standard resection for pancreatic and periampullary adenocarcinoma (2021) · Cochrane | HR 0.12 | 7 studies · 823 participants | Very low |
Extended vs standard lymph node resection Overall survival (3‐year · people with pancreatic and periampullary adenocarcinoma Extended lymph node resection versus standard resection for pancreatic and periampullary adenocarcinoma (2021) · Cochrane | HR 0.12 | 7 studies · 823 participants | Very low |
Extended vs standard lymph node resection Postoperative mortality (duration of · people with pancreatic and periampullary adenocarcinoma Extended lymph node resection versus standard resection for pancreatic and periampullary adenocarcinoma (2021) · Cochrane | Peto OR 1.2 [0.51, 2.8] | 7 studies · 843 participants | Low |
Extended vs standard lymph node resection Operating time · people with pancreatic and periampullary adenocarcinoma Extended lymph node resection versus standard resection for pancreatic and periampullary adenocarcinoma (2021) · Cochrane | no estimate extracted | 5 studies · 670 participants | Moderate |
Extended vs standard lymph node resection Blood loss · people with pancreatic and periampullary adenocarcinoma Extended lymph node resection versus standard resection for pancreatic and periampullary adenocarcinoma (2021) · Cochrane | no estimate extracted | 2 studies · 463 participants | Very low |
Extended vs standard lymph node resection Lymph nodes retrieved · people with pancreatic and periampullary adenocarcinoma Extended lymph node resection versus standard resection for pancreatic and periampullary adenocarcinoma (2021) · Cochrane | no estimate extracted | 5 studies · 670 participants | Moderate |
Extended vs standard lymph node resection Positive resection margins (R1 + R2) · people with pancreatic and periampullary adenocarcinoma Extended lymph node resection versus standard resection for pancreatic and periampullary adenocarcinoma (2021) · Cochrane | RR 0.81 [0.58, 1.13] | 6 studies · 783 participants | Very low |
Laparoscopic pyloromyotomy vs open pyloromyotomy Mucosal perforation · infants (< 1 year of age) with hypertrophic pyloric stenosis Open versus laparoscopic pyloromyotomy for pyloric stenosis (2021) · Cochrane | RR 1.6 [0.49, 5.26] | 7 studies · 720 participants | Low |
Laparoscopic pyloromyotomy vs open pyloromyotomy Incomplete pyloromyotomy · infants (< 1 year of age) with hypertrophic pyloric stenosis Open versus laparoscopic pyloromyotomy for pyloric stenosis (2021) · Cochrane | RR 7.37 [0.92, 59.11] | 4 studies · 502 participants | Low |
Laparoscopic pyloromyotomy vs open pyloromyotomy Postoperative wound infection or abscess formation · infants (< 1 year of age) with hypertrophic pyloric stenosis Open versus laparoscopic pyloromyotomy for pyloric stenosis (2021) · Cochrane | RR 0.59 [0.24, 1.45] | 7 studies · 720 participants | Very low |
Laparoscopic pyloromyotomy vs open pyloromyotomy Postoperative incisional hernia · infants (< 1 year of age) with hypertrophic pyloric stenosis Open versus laparoscopic pyloromyotomy for pyloric stenosis (2021) · Cochrane | RR 1.01 [0.11, 9.53] | 4 studies · 382 participants | Very low |
Laparoscopic pyloromyotomy vs open pyloromyotomy Length of hospital stay · infants (< 1 year of age) with hypertrophic pyloric stenosis Open versus laparoscopic pyloromyotomy for pyloric stenosis (2021) · Cochrane | no estimate extracted | 5 studies · 562 participants | Very low |
Laparoscopic pyloromyotomy vs open pyloromyotomy Time to full feeds · infants (< 1 year of age) with hypertrophic pyloric stenosis Open versus laparoscopic pyloromyotomy for pyloric stenosis (2021) · Cochrane | no estimate extracted | 6 studies · 622 participants | Very low |
Laparoscopic pyloromyotomy vs open pyloromyotomy Operating time · infants (< 1 year of age) with hypertrophic pyloric stenosis Open versus laparoscopic pyloromyotomy for pyloric stenosis (2021) · Cochrane | no estimate extracted | 6 studies · 622 participants | Very low |
Roux‐en‐Y vs Billroth‐I after distal gastrectomy Health‐related quality of life · people undergoing distal gastrectomy for gastric cancer Roux‐en‐Y versus Billroth‐I reconstruction after distal gastrectomy for gastric cancer (2021) · Cochrane | no estimate extracted | 6 studies · 695 participants | Low |
Roux‐en‐Y vs Billroth‐I after distal gastrectomy Incidence of anastomotic leakage · people undergoing distal gastrectomy for gastric cancer Roux‐en‐Y versus Billroth‐I reconstruction after distal gastrectomy for gastric cancer (2021) · Cochrane | RR 0.63 [0.16, 2.53] | 5 studies · 711 participants | Very low |
Roux‐en‐Y vs Billroth‐I after distal gastrectomy Loss of body weight · people undergoing distal gastrectomy for gastric cancer Roux‐en‐Y versus Billroth‐I reconstruction after distal gastrectomy for gastric cancer (2021) · Cochrane | no estimate extracted | 4 studies · 541 participants | Low |
Roux‐en‐Y vs Billroth‐I after distal gastrectomy Incidence of bile reflux · people undergoing distal gastrectomy for gastric cancer Roux‐en‐Y versus Billroth‐I reconstruction after distal gastrectomy for gastric cancer (2021) · Cochrane | RR 0.4 [0.25, 0.63] | 4 studies · 399 participants | Moderate |
Roux‐en‐Y vs Billroth‐I after distal gastrectomy Length of hospital stay · people undergoing distal gastrectomy for gastric cancer Roux‐en‐Y versus Billroth‐I reconstruction after distal gastrectomy for gastric cancer (2021) · Cochrane | no estimate extracted | 7 studies · 894 participants | Very low |
Roux‐en‐Y vs Billroth‐I after distal gastrectomy Postoperative morbidity · people undergoing distal gastrectomy for gastric cancer Roux‐en‐Y versus Billroth‐I reconstruction after distal gastrectomy for gastric cancer (2021) · Cochrane | RR 1.47 [1.02, 2.11] | 7 studies · 891 participants | Low |
More frequent (less than eight hours) vs less frequent (eight hours or greater) monitoring of gastric residual volume Mortality (at the end of · adults receiving EN via nasogastric tube or gastrostomy tube Monitoring of gastric residual volume during enteral nutrition (2021) · Cochrane | RR 0.91 [0.6, 1.37] | 2 studies · 417 participants | Very low |