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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.
759 questions in 57 reviews · Colorectal
current versionsNo studies 91 · 12%Ungraded 12 · 1.6%Very low 209 · 27.5%Low 229 · 30.2%Moderate 160 · 21.1%High 58 · 7.6%
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 |
|---|---|---|---|
Preoperative parenteral nutrition vs usual care or control Non‐infectious complications · people undergoing gastrointestinal surgery Preoperative nutrition therapy in people undergoing gastrointestinal surgery (2024) · Cochrane | RR 0.61 [0.36, 1.02] | 3 studies · 260 participants | Very low |
Immune‐enhancing supplements (oral or enteral) vs usual care or control Infectious complications recorded up to 30 days postdischarge · people undergoing gastrointestinal surgery Preoperative nutrition therapy in people undergoing gastrointestinal surgery (2024) · Cochrane | RR 0.74 [0.53, 1.04] | 7 studies · 925 participants | Low |
Immune‐enhancing supplements (oral or enteral) vs usual care or control Length of hospital stay (days) · people undergoing gastrointestinal surgery Preoperative nutrition therapy in people undergoing gastrointestinal surgery (2024) · Cochrane | no estimate extracted | 6 studies · 688 participants | Low |
Immune‐enhancing supplements (oral or enteral) vs usual care or control Adverse effects · people undergoing gastrointestinal surgery Preoperative nutrition therapy in people undergoing gastrointestinal surgery (2024) · Cochrane | no estimate extracted | 3 studies · 399 participants | Ungraded |
Oral nutritional supplements vs usual care or control Non‐infectious complications recorded up to 30 days postdischarge · people undergoing gastrointestinal surgery Preoperative nutrition therapy in people undergoing gastrointestinal surgery (2024) · Cochrane | RR 0.9 [0.67, 1.2] | 5 studies · 473 participants | Low |
Oral nutritional supplements vs usual care or control Infectious complications recorded up to 30 days postdischarge · people undergoing gastrointestinal surgery Preoperative nutrition therapy in people undergoing gastrointestinal surgery (2024) · Cochrane | RR 0.88 [0.6, 1.27] | 5 studies · 473 participants | Very low |
Oral nutritional supplements vs usual care or control Length of hospital stay (days) · people undergoing gastrointestinal surgery Preoperative nutrition therapy in people undergoing gastrointestinal surgery (2024) · Cochrane | no estimate extracted | 3 studies · 299 participants | Low |
Oral nutritional supplements vs usual care or control Adverse effects · people undergoing gastrointestinal surgery Preoperative nutrition therapy in people undergoing gastrointestinal surgery (2024) · Cochrane | no estimate extracted | 4 studies · 373 participants | Ungraded |
Preoperative parenteral nutrition vs usual care or control Infectious complications · people undergoing gastrointestinal surgery Preoperative nutrition therapy in people undergoing gastrointestinal surgery (2024) · Cochrane | RR 0.98 [0.53, 1.8] | 3 studies · 260 participants | Very low |
Preoperative parenteral nutrition vs usual care or control Length of hospital stay (days) · people undergoing gastrointestinal surgery Preoperative nutrition therapy in people undergoing gastrointestinal surgery (2024) · Cochrane | no estimate extracted | 2 studies · 135 participants | Very low |
Preoperative parenteral nutrition vs usual care or control Adverse effects · people undergoing gastrointestinal surgery Preoperative nutrition therapy in people undergoing gastrointestinal surgery (2024) · Cochrane | no estimate extracted | 3 studies · 260 participants | Ungraded |
Preoperative enteral nutrition (standard formula) vs usual care or control Non‐infectious complications · people undergoing gastrointestinal surgery Preoperative nutrition therapy in people undergoing gastrointestinal surgery (2024) · Cochrane | no estimate extracted | NR | No studies |
Preoperative enteral nutrition (standard formula) vs usual care or control Infectious complications · people undergoing gastrointestinal surgery Preoperative nutrition therapy in people undergoing gastrointestinal surgery (2024) · Cochrane | RR 0.9 [0.59, 1.38] | 2 studies · 126 participants | Very low |
Preoperative enteral nutrition (standard formula) vs usual care or control Length of hospital stay (days) · people undergoing gastrointestinal surgery Preoperative nutrition therapy in people undergoing gastrointestinal surgery (2024) · Cochrane | no estimate extracted | 2 studies · 126 participants | Very low |
Preoperative enteral nutrition (standard formula) vs usual care or control Adverse effects · people undergoing gastrointestinal surgery Preoperative nutrition therapy in people undergoing gastrointestinal surgery (2024) · Cochrane | no estimate extracted | 1 study · 26 participants | Ungraded |
Immune‐enhancing supplements (oral or enteral) vs usual care or control Non‐ infectious complications recorded up to 30 days postdischarge · people undergoing gastrointestinal surgery Preoperative nutrition therapy in people undergoing gastrointestinal surgery (2024) · Cochrane | RR 0.79 [0.62, 1] | 8 studies · 1020 participants | Low |
Early vs delayed open or laparoscopic appendicectomy Overall morbidity Median · paediatric and adult participants with appendiceal phlegmon Early versus delayed appendicectomy for appendiceal phlegmon or abscess (2024) · Cochrane | RR 0.74 [0.19, 2.86] | 3 studies · 146 participants | Very low |
Early vs delayed laparoscopic appendicectomy Abdominal abscess · paediatric participants with appendiceal abscess Early versus delayed appendicectomy for appendiceal phlegmon or abscess (2024) · Cochrane | no estimate extracted | NR | No studies |
Early vs delayed laparoscopic appendicectomy Faecal fistula · paediatric participants with appendiceal abscess Early versus delayed appendicectomy for appendiceal phlegmon or abscess (2024) · Cochrane | no estimate extracted | NR | No studies |
Early vs delayed laparoscopic appendicectomy Mortality · paediatric participants with appendiceal abscess Early versus delayed appendicectomy for appendiceal phlegmon or abscess (2024) · Cochrane | no estimate extracted | 1 study · 40 participants | Very low |
Early vs delayed laparoscopic appendicectomy Total length of hospital stay (days) · paediatric participants with appendiceal abscess Early versus delayed appendicectomy for appendiceal phlegmon or abscess (2024) · Cochrane | no estimate extracted | 1 study · 40 participants | Very low |
Early vs delayed laparoscopic appendicectomy Time away from normal activities (days) · paediatric participants with appendiceal abscess Early versus delayed appendicectomy for appendiceal phlegmon or abscess (2024) · Cochrane | no estimate extracted | NR | No studies |
Early vs delayed open or laparoscopic appendicectomy Wound infection Median · paediatric and adult participants with appendiceal phlegmon Early versus delayed appendicectomy for appendiceal phlegmon or abscess (2024) · Cochrane | RR 0.99 [0.48, 2.02] | 7 studies · 788 participants | Very low |
Early vs delayed open or laparoscopic appendicectomy Abdominal abscess Median · paediatric and adult participants with appendiceal phlegmon Early versus delayed appendicectomy for appendiceal phlegmon or abscess (2024) · Cochrane | RR 0.26 [0.08, 0.8] | 4 studies · 626 participants | Very low |
Early vs delayed open or laparoscopic appendicectomy Faecal fistula Median · paediatric and adult participants with appendiceal phlegmon Early versus delayed appendicectomy for appendiceal phlegmon or abscess (2024) · Cochrane | RR 1.75 [0.36, 8.49] | 5 studies · 388 participants | Very low |
Early vs delayed open or laparoscopic appendicectomy Mortality Median · paediatric and adult participants with appendiceal phlegmon Early versus delayed appendicectomy for appendiceal phlegmon or abscess (2024) · Cochrane | no estimate extracted | 7 studies · 788 participants | Very low |
Early vs delayed open or laparoscopic appendicectomy Total length of hospital stay (days) · paediatric and adult participants with appendiceal phlegmon Early versus delayed appendicectomy for appendiceal phlegmon or abscess (2024) · Cochrane | no estimate extracted | 5 studies · 680 participants | Very low |
Early vs delayed open or laparoscopic appendicectomy Time away from normal activities (days) Median · paediatric and adult participants with appendiceal phlegmon Early versus delayed appendicectomy for appendiceal phlegmon or abscess (2024) · Cochrane | MD 5 [1.52, 8.48] | 1 study · 40 participants | Very low |
Early vs delayed laparoscopic appendicectomy Overall morbidity · paediatric participants with appendiceal abscess Early versus delayed appendicectomy for appendiceal phlegmon or abscess (2024) · Cochrane | no estimate extracted | NR | No studies |
Early vs delayed laparoscopic appendicectomy Wound infection · paediatric participants with appendiceal abscess Early versus delayed appendicectomy for appendiceal phlegmon or abscess (2024) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings table ‐ Purse‐string skin closure vs linear skin closure Surgical site infection · people undergoing stoma reversal Purse‐string skin closure versus linear skin closure in people undergoing stoma reversal (2024) · Cochrane | OR 0.17 [0.09, 0.29] | 9 studies · 757 participants | Moderate |
Summary of findings table ‐ Purse‐string skin closure vs linear skin closure Participant satisfaction (very satisfied or satisfied) · people undergoing stoma reversal Purse‐string skin closure versus linear skin closure in people undergoing stoma reversal (2024) · Cochrane | OR 20.11 [1.09, 369.88] | 2 studies · 122 participants | Low |
Summary of findings table ‐ Purse‐string skin closure vs linear skin closure Incisional hernia · people undergoing stoma reversal Purse‐string skin closure versus linear skin closure in people undergoing stoma reversal (2024) · Cochrane | OR 0.51 [0.07, 3.7] | 4 studies · 297 participants | Very low |
Summary of findings table ‐ Purse‐string skin closure vs linear skin closure Operative time · people undergoing stoma reversal Purse‐string skin closure versus linear skin closure in people undergoing stoma reversal (2024) · Cochrane | no estimate extracted | 6 studies · 460 participants | Very low |
Summary of findings table ‐ Uncut Roux‐en‐Y reconstruction vs Billroth II reconstruction after distal gastrectomy Health‐related quality of life ‐ not reported · people undergoing distal gastrectomy for gastric cancer Uncut Roux‐en‐Y reconstruction after distal gastrectomy for gastric cancer (2024) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings table ‐ Uncut Roux‐en‐Y reconstruction vs Roux‐en‐Y reconstruction after distal gastrectomy Incidence of anastomotic leakage · people undergoing distal gastrectomy for gastric cancer Uncut Roux‐en‐Y reconstruction after distal gastrectomy for gastric cancer (2024) · Cochrane | RR 0.34 [0.05, 2.08] | 2 studies · 213 participants | Very low |
Summary of findings table ‐ Uncut Roux‐en‐Y reconstruction vs Roux‐en‐Y reconstruction after distal gastrectomy Changes in body weight from baseline ‐ not reported · people undergoing distal gastrectomy for gastric cancer Uncut Roux‐en‐Y reconstruction after distal gastrectomy for gastric cancer (2024) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings table ‐ Uncut Roux‐en‐Y reconstruction vs Roux‐en‐Y reconstruction after distal gastrectomy Incidence of bile reflux · people undergoing distal gastrectomy for gastric cancer Uncut Roux‐en‐Y reconstruction after distal gastrectomy for gastric cancer (2024) · Cochrane | RR 10.74 [3.52, 32.76] | 1 study · 108 participants | Very low |
Summary of findings table ‐ Uncut Roux‐en‐Y reconstruction vs Roux‐en‐Y reconstruction after distal gastrectomy Incidence of remnant gastritis · people undergoing distal gastrectomy for gastric cancer Uncut Roux‐en‐Y reconstruction after distal gastrectomy for gastric cancer (2024) · Cochrane | RR 1.18 [0.69, 2.01] | 3 studies · 361 participants | Very low |
Summary of findings table ‐ Uncut Roux‐en‐Y reconstruction vs Roux‐en‐Y reconstruction after distal gastrectomy Incidence of oesophagitis · people undergoing distal gastrectomy for gastric cancer Uncut Roux‐en‐Y reconstruction after distal gastrectomy for gastric cancer (2024) · Cochrane | RR 0.82 [0.53, 1.26] | 3 studies · 361 participants | Very low |
Summary of findings table ‐ Uncut Roux‐en‐Y reconstruction vs Billroth II reconstruction after distal gastrectomy Major postoperative complications · people undergoing distal gastrectomy for gastric cancer Uncut Roux‐en‐Y reconstruction after distal gastrectomy for gastric cancer (2024) · Cochrane | RR 0.98 [0.24, 4.05] | 2 studies · 282 participants | Very low |
Summary of findings table ‐ Uncut Roux‐en‐Y reconstruction vs Billroth II reconstruction after distal gastrectomy Incidence of anastomotic leakage · people undergoing distal gastrectomy for gastric cancer Uncut Roux‐en‐Y reconstruction after distal gastrectomy for gastric cancer (2024) · Cochrane | RR 0.64 [0.29, 1.44] | 3 studies · 615 participants | Very low |
Summary of findings table ‐ Uncut Roux‐en‐Y reconstruction vs Billroth II reconstruction after distal gastrectomy Changes in body weight from baseline · people undergoing distal gastrectomy for gastric cancer Uncut Roux‐en‐Y reconstruction after distal gastrectomy for gastric cancer (2024) · Cochrane | no estimate extracted | 2 studies · 233 participants | Low |
Summary of findings table ‐ Uncut Roux‐en‐Y reconstruction vs Billroth II reconstruction after distal gastrectomy Incidence of bile reflux · people undergoing distal gastrectomy for gastric cancer Uncut Roux‐en‐Y reconstruction after distal gastrectomy for gastric cancer (2024) · Cochrane | RR 0.67 [0.55, 0.83] | 1 study · 141 participants | Low |
Summary of findings table ‐ Uncut Roux‐en‐Y reconstruction vs Billroth II reconstruction after distal gastrectomy Incidence of remnant gastritis · people undergoing distal gastrectomy for gastric cancer Uncut Roux‐en‐Y reconstruction after distal gastrectomy for gastric cancer (2024) · Cochrane | RR 0.27 [0.01, 5.06] | 2 studies · 265 participants | Very low |
Summary of findings table ‐ Uncut Roux‐en‐Y reconstruction vs Billroth II reconstruction after distal gastrectomy Incidence of oesophagitis ‐ not reported · people undergoing distal gastrectomy for gastric cancer Uncut Roux‐en‐Y reconstruction after distal gastrectomy for gastric cancer (2024) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings table ‐ Uncut Roux‐en‐Y reconstruction vs Roux‐en‐Y reconstruction after distal gastrectomy Health‐related quality of life ‐ not reported · people undergoing distal gastrectomy for gastric cancer Uncut Roux‐en‐Y reconstruction after distal gastrectomy for gastric cancer (2024) · Cochrane | no estimate extracted | NR | No studies |
Summary of findings table ‐ Uncut Roux‐en‐Y reconstruction vs Roux‐en‐Y reconstruction after distal gastrectomy Major postoperative complications · people undergoing distal gastrectomy for gastric cancer Uncut Roux‐en‐Y reconstruction after distal gastrectomy for gastric cancer (2024) · Cochrane | RR 4.74 [0.23, 97.08] | 2 studies · 256 participants | Very low |
Antibiotics vs surgery Mortality · adults with uncomplicated appendicitis Appendectomy versus antibiotic treatment for acute appendicitis (2024) · Cochrane | OR 0.51 [0.05, 4.95] | 5 studies · 2377 participants | Very low |
Antibiotics vs surgery Success of treatment · adults with uncomplicated appendicitis Appendectomy versus antibiotic treatment for acute appendicitis (2024) · Cochrane | RR 0.91 [0.87, 0.96] | 7 studies · 2471 participants | Low |