Cochrane Review Group

Colorectal

57 systematic reviews in Colorectal ask 759 questions. 12% have no studies to answer them, 27.5% rest on very low certainty evidence and 28.7% reach moderate or high certainty.

Reviews

Questions

759

current versions

No studies

12%

Moderate or high

28.7%

No 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.

Search questions in Colorectal

Thinnest evidence

All no studies and very low questions

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
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
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 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
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

Reviews 57

Prosthetic mesh placement for the prevention of parastomal herniation

Jones, HG, Rees, M, et al. · Cochrane Database of Systematic Reviews · 2018

Colorectal

Thinnest evidence

Reviews 57

Prosthetic mesh placement for the prevention of parastomal herniation

Mesh versus non‐mesh for inguinal and femoral hernia repair

Daikenchuto for reducing postoperative ileus in patients undergoing elective abdominal surgery

Survival differences with immediate versus delayed chemotherapy for asymptomatic incurable metastatic colorectal cancer

Dietary fibre for the prevention of recurrent colorectal adenomas and carcinomas

Closure methods for laparotomy incisions for preventing incisional hernias and other wound complications

Closure methods of the appendix stump for complications during laparoscopic appendectomy

Management for intussusception in children

Second‐line systemic therapy for metastatic colorectal cancer

Epidermal growth factor receptor (EGFR) inhibitors for metastatic colorectal cancer

Oral versus intravenous fluoropyrimidines for colorectal cancer

Laparoscopic versus open resection for sigmoid diverticulitis

Mesalamine (5‐ASA) for the prevention of recurrent diverticulitis

Mesh fixation with glue versus suture for chronic pain and recurrence in Lichtenstein inguinal hernioplasty

Chromoscopy versus conventional endoscopy for the detection of polyps in the colon and rectum

Heated insufflation with or without humidification for laparoscopic abdominal surgery

Irinotecan chemotherapy combined with fluoropyrimidines versus irinotecan alone for overall survival and progression‐free survival in patients with advanced and/or metastatic colorectal cancer

Chewing gum for postoperative recovery of gastrointestinal function

Combination chemotherapy versus single‐agent chemotherapy during preoperative chemoradiation for resectable rectal cancer

Water infusion versus air insufflation for colonoscopy

Antimicrobial prophylaxis for colorectal surgery

Laparoscopic versus open total mesorectal excision for rectal cancer

Flexible sigmoidoscopy versus faecal occult blood testing for colorectal cancer screening in asymptomatic individuals

Non surgical therapy for anal fissure

Phlebotonics for haemorrhoids