Table 2.

The main phases of bypass procedures, by centre

Phase	Lay description of the purpose of each phase	Order phase performed
		Centre A	Centre B
Establishing a pneumoperitoneum and insertion of ports	To provide access to the abdominal cavity	1	1
Creation of the Roux limb	To divert the passage of food away from the first portion of small bowel	2	3
Jejuno-jejunostomy		3	5
Gastric pouch formation	To reduce the stomach volume	4	2
Gastro-jejunostomy formation	To join the stomach pouch to the end of the diverted portion of bowel	5	4
Closure	To reconstruct the layers of fat and muscle, re-creating how they looked before the operation	6	6