Appendix 1. Glossary of terms

Ampullary Carcinoma: A cancerous growth that occurs at the Ampulla of Vater. This is the area in the small bowel where the biliary system drains into the GI tract.

Anastomosis: An anastomosis is a surgical connection (join) between two tubular structures. In a gastrojejunostomy, the anastomosis is between the stomach (gastric) and jejunum (small bowel).

Anastomotic Leak: The breakdown in the join between two structures. This results in leakage of the contents of the structures into the abdominal cavity resulting in significant problems.

Benign: This refers to conditions that are not cancerous.

Bile duct: The tubular structures which drain bile (greenish liquid which is necessary for the digestion and absorption of fat) from the liver and gallbladder to the small bowel.

Biliary Obstruction: Blockage of the bile ducts due to any cause, which includes cancers. This typically results in jaundice (yellowing of the skin).

Cholangiocarcinoma: A cancer (malignant growth) of the bile ducts.

Distal: The area that is at the bottom end. For example: the distal end of the stomach is the bottom end of the stomach.

Duodenum: The first part of the small bowel which begins after the stomach.

Electrolyte Imbalance: A change in the concentration of salts in the blood (e.g.: potassium, sodium) which are essential for normal cellular function. This can occur, for example, after vomiting.

Epigastrium: This describes the area of the body that sits below the chest in the centre. Epigastric pain refers to pain that is felt in this area.

Endoscope: The instrument used to look inside the stomach and small bowel during an endoscopy. It consists of a hollow tube, about the size of your 5^th finger, with a light and camera. Instruments can be passed down the tube to take tissue samples from the stomach and small bowel.

Endoscopy: Endoscopy is the process of looking inside the body with a camera attached to a scope. In gastroscopy, the camera is inserted via the mouth to the stomach and small bowel.

Fluoroscopic: This relates to the radiological technique which uses specialised dye and x‐ray. It is typically used to monitor the placement of devices, including stents, in the body as it allows exact placement to be monitored.

Gastric: Refers to the stomach.

Gastric Outlet: The area of the stomach through which food passes on its route to the small bowel. The gastric outlet is in the part of the stomach that is known as the pylorus.

Gastric Outlet Obstruction (GOO): This describes the obstruction to the passage of food and liquid at the distal end of the stomach, also known as the gastric outlet.

Gastrojejunostomy: This describes a connection between the stomach (gastric) and small bowel (jejunum).

Helicobacter pylori: This is the name given to the bacteria that has been shown to be associated with peptic ulcer disease.

Intra‐luminal: This refers to the inside of a hollow structure.

Jaundice: The yellow discoloration of the skin which can occur as a result of reduced drainage of bile (or biliary obstruction).

Jejunum: The middle part of the small bowel which is distal to the duodenum.

Laparoscopic: This is also referred to as minimal access surgery. This is surgery via small incisions on the abdomen through which specialised instruments are passed. This alleviates the need for large incisions on the abdomen.

Lateral: This term is used to describe the position of a structure or object. Lateral describes objects or structures to the side, whereas, medial describes objects or structure lying along the middle or centre.

Lymphoma: This is a cancer that affects the lymph nodes of the body.

Malignant: This refers to a cancerous process.

Metastatic Disease: This is disease that has spread from the organ that it originates from to lymph nodes or other organs around the body. Metastatic disease typically refers to an advanced stage of cancer.

Migration: the movement from the original position to another position. In stent migration, this refers to movement of the stent from the position it was placed to a different, and typically worse, position.

Morbidity: Complications or events that impact on the patients’ ability to function and return to their normal level of functioning. For example; a chest infection that prevents walking is said to have caused morbidity.

Mortality: Death rate

Occlusion: Blockage. This can be partial or complete.

Palliation: The control of symptoms without the treatment of, or attempt to treat, the underlying cause of the symptoms.

Pathological: The result of the underlying disease process.

Peptic Ulcer: A break or erosion in the lining of the stomach or small bowel.

Perforation: A small hole that appears in part of the GI tract as a cause of disease or an intervention. For example; a gastric perforation is a hole in the stomach from which stomach contents can escape into the rest of the abdominal cavity.

Peri‐operative: At the time of operation. For example; a peri‐operative complication would be something at occurs during the operation.

Physiological Reserve: This refers to the capacity, predominantly in terms of heart and lung function, that a person has to withstand various insults to the body.

Pneumoperitoneum: In laparoscopic surgery, carbon dioxide is placed inside the abdomen to create space. This is known as a pneumoperitoneum.

Port: A port is a specialised device used in laparoscopic surgery through which the specialised instruments are passed. A port is either 5mm or 12mm in size and, thus, the incisions are approximately this size.

Post‐prandial: Occurs following eating.

Proton‐pump Inhibitor (PPI): A medicine that reduces the production of acid in the stomach. This helps to treat ulcerations in the stomach.

Pylorus: The name given to the distal end of the stomach where the gastric outlet sits. A pyloric carcinoma is a cancer that grows at the pylorus.

Roux‐en‐y anastomosis: This describes a surgically created end‐to‐side anastomosis, usually between the stomach and small bowel.

Self Expanding Metal Stent (SEMS): A stent which is able to expand and fit the patient depending on the space and external forces encountered.

Stent: A hollow tube, wither plastic or metal, or self‐expanding, which is used to keep a passageway within the body open.

Terminal: This refers to conditions for which there is no cure and for which this will be the cause of death. This does not mean that the symptoms cannot be treated or improved.

Umbilicus: The area at the belly‐button or navel.

Appendix 2. CENTRAL search strategy

1. exp Gastric Outlet Obstruction/

2. (gastric adj2 outlet adj2 obstruction$).mp. [mp=title, abstract, subject headings, heading word, drug trade name, original title, device manufacturer, drug manufacturer name]

3. GOO.mp.

4. or/1‐3

5. Stents/

6. stent$.mp.

7. (endoscop$ adj2 clip$).mp. [mp=title, abstract, subject headings, heading word, drug trade name, original title, device manufacturer, drug manufacturer name]

8. Equipment Design/

9. Prosthesis Design/

10. endoscopy, gastrointestinal/ or duodenoscopy/ or gastroscopy/

11. or/5‐10

12. (surgical adj2 palliation).mp. [mp=title, abstract, subject headings, heading word, drug trade name, original title, device manufacturer, drug manufacturer name]

13. Palliative Care/mt [Methods]

14. Surgical Instruments/

15. or/12‐14

16. 4 and (11 or 15)

Appendix 3. MEDLINE search strategy

(We had drafted a MEDLINE search strategy for a previous version of this protocol, which has been included below, for future revision)

1. randomized controlled trial.pt.

2. controlled clinical trial.pt.

3. randomized.ab.

4. placebo.ab.

5. drug therapy.fs.

6. randomly.ab.

7. trial.ab.

8. groups.ab.

9. or/1‐8

10. exp animals/ not humans.sh.

11. 9 not 10

12. exp Gastric Outlet Obstruction/

13. (gastric adj2 outlet adj2 obstruction$).mp. [mp=title, original title, abstract, name of substance word, subject heading word, unique identifier]

14. GOO.mp.

15. or/12‐14

16. Stents/

17. stent$.mp.

18. (endoscop$ adj2 clip$).mp. [mp=title, original title, abstract, name of substance word, subject heading word, unique identifier]

19. Equipment Design/

20. Prosthesis Design/

21. endoscopy, gastrointestinal/ or duodenoscopy/ or gastroscopy/

22. or/16‐21

23. (surgical adj2 palliation).mp. [mp=title, original title, abstract, name of substance word, subject heading word, unique identifier]

24. Palliative Care/mt [Methods]

25. Surgical Instruments/

26. or/23‐25

27. 15 and (22 or 26)

28. 11 and 27

Appendix 4. EMBASE search strategy

1. Clinical trial/

2. Randomized controlled trial/

3. Randomization/

4. Single‐Blind Method/

5. Double‐Blind Method/

6. Cross‐Over Studies/

7. Random Allocation/

8. Placebo/

9. Randomi?ed controlled trial$.tw.

10. Rct.tw.

11. Random allocation.tw.

12. Randomly allocated.tw.

13. Allocated randomly.tw.

14. (allocated adj2 random).tw.

15. Single blind$.tw.

16. Double blind$.tw.

17. ((treble or triple) adj blind$).tw.

18. Placebo$.tw.

19. Prospective study/

20. or/1‐19

21. Case study/

22. Case report.tw.

23. Abstract report/ or letter/

24. or/21‐23

25. 20 not 24

26. stomach obstruction/

27. (gastric adj2 outlet adj2 obstruction$).mp. [mp=title, abstract, subject headings, heading word, drug trade name, original title, device manufacturer, drug manufacturer name]

28. GOO.mp.

29. or/26‐28

30. stent$.mp.

31. (endoscop$ adj2 clip$).mp. [mp=title, abstract, subject headings, heading word, drug trade name, original title, device manufacturer, drug manufacturer name]

32. Equipment Design/

33. prosthesis/

34. gastrointestinal endoscopy/ or duodenoscopy/ or gastroscopy/

35. or/30‐34

36. (surgical adj2 palliation).mp. [mp=title, abstract, subject headings, heading word, drug trade name, original title, device manufacturer, drug manufacturer name]

37. palliative therapy/ or cancer palliative therapy/

38. surgical instrument/

39. metal implantation/

40. or/36‐39

41. 29 and (35 or 40)

42. 25 and 41