Table 1.

Definitions of the seven surgical phases (P0–P6)

Phase	Task	Start point/end point
P0	Other	Extracorporeal operation, trocar insertion, adhesiolysis, cleaning, other recovery, hemostasis, unexpected suture, drain insertion, trocar removal, etc.
P1	Preparation	Start: lifting gallbladder with grasping forceps
		End: completed clearance around the gallbladder
P2	Calot’s triangle dissection	Start: incising the gallbladder neck
		End: achieved critical view of safety
P3	Clipping and cutting	Start: inserting a clipping device to cut the cystic duct or artery
		End: completed cutting of the cystic duct or artery
P4	Gallbladder dissection	Start: dissecting gallbladder from the liver bed
		End: released gallbladder from the liver bed
P5	Gallbladder retrieving	Start: inserting retrieving bag
		End: removed the retrieving bag
P6	Cleaning and coagulation	Start: inserting a suction device
		End: removed the suction device