Suppl. Table 1: Treatment protocol adopted in included trials
Trial
Aprea et al 25
Asakuma et al26
Bucher et al27
Cao et al 28
Lai et al 29
Lee et al 30
Lirici et al31
Ma et al 32
Phillips et al33
Tsiomoyiannis et al 34
Zheng et al35
Single incision laparoscopic cholecystectomy group

TriPort® Laparoscopic Access Device manufactured
by Olympus was used

1.5 – 2 cm transumbilical incision

Open pneumoperitoneum approach

0°laparoscope with flexible head

Cephalad retraction of gallbladder through abdominal
wall 2/0 polypropylene stitch

Routine on-table cholangiography

French technique for laparoscopic

1.5 – 2 cm transumbilical incision

Alexis® and Surgical glove for multi-port access

Falciform ligament suture retraction

TriPort® Advanced Surgical Concepts (Ireland) and 5
mm flexible LESS instruments

1.5 cm transumbilical incision

Open pneumoperitoneum approach

0 degree camera with flexible head

Routine on-table cholangiography

Reverse Trendelenburg position

21.6±2.4 mm transumbilical vertical incision

Veress needle pneumoperitoneum approach

30° laparoscope

1 x 10 mm and 2 x 5 mm ports through same
transumbilical incision

Cephalad retraction of gallbladder through abdominal
wall 2/0 polypropylene stitch

Reverse Trendelenburg position

17.6±0.29 mm umbilical incision

SILS (Covidien Inc, Norwalk, CT) flexible
laparoscopic port for three instruments

Open pneumoperitoneum approach

30° laparoscope or flexible 0 scope°

QuadraPort® Laparoscopic Access Device
manufactured by LAGIS was used

15.7± 1 transumbilical vertical incision

30° laparoscope

Cephalad retraction of gallbladder through abdominal
wall 2/0 polypropylene stitch

TriPort® Laparoscopic Access Device manufactured
by Olympus was used

18.8(13-25) mm transumbilical vertical incision

1.5 to 2 cm umbilical incision with use of Triport®

Standard SILC approach

SILS™ port system was used

Selective on-table cholangiography

French position

Open pneumoperitoneum approach

12 mm umbilical incision

45° laparoscope

Cephalad retraction of gallbladder through abdominal
wall 2/0 polypropylene stitch

SILC (LESS) procedure with use of Triport®

45° laparoscope
Conventional laparoscopic cholecystectomy group

Reverse Trendelenburg position

Open pneumoperitoneum approach

30° laparoscope

French technique for laparoscopic
cholecystectomy



Routine on-table cholangiography
French technique for laparoscopic
1 x 12 mm and 3 x 5 mm ports




Routine on-table cholangiography
2 x 10 mm and 2 x 5 mm ports
30° laparoscope
Open pneumoperitoneum approach



2 x 10 mm and 1 x 5 mm ports
Veress needle pneumoperitoneum approach
30.8±2.8 mm combined incisions length




2 x 10 mm and 2 x 5 mm ports
30° laparoscope
Open pneumoperitoneum approach
22.5±0.05 mm combined incisions length



1 x 10 mm and 3 x 3 mm ports
30° laparoscope
20.9±1.4 mm combined incisions length






French technique for positioning and ports
14.31(10-23) mm combined incisions length
2 x 12 mm and 2 x 5 mm ports
1 x 10 mm and 3 x 5 mm ports
Standard cholecystectomy approach
1 or 2 x 10 or 12 mm and 2 or 3 x 5 mm ports



Reverse Trendelenburg position
Open pneumoperitoneum approach
1 x 11 mm and 3 x 5 mm ports


2 x 10 mm and 2 x 5 mm ports
Standard cholecystectomy approach
Suppl. Table 2: Possible causes of heterogeneity
Clinical causes of heterogeneity








Methodological causes of heterogeneity
 Different inclusion (ideal patients)and
Recruited patients with variable levels of
exclusion criteria
gallbladder disease e.g. Nassar classification
 Use of variable randomization techniques
Inconsistent duration of follow up among trials
 Inadequate power calculations
Use of different pain scoring scales such as
 Absence of adequate blinding
Visual Analogue Scale 1-100, Visual
 Inadequate reporting of lost to follow up
Analogue Scale 1-10 and pain measurement in
 Lack of intention to treat analysis
the form of mild, moderate and severe.
 Variable methods of concealment
Use of different durations to record pain
among included trials such as postoperative
pain at 1 hour, 6 hours, day 1, day 7, day 21
Use of different cosmetic scoring scales such
as Visual Analogue Scale 1-100, Visual
Analogue Scale 1-10 and patient satisfaction
levels in the form of health-related quality of
life questionnaires.
Variable use of preoperative antibiotics
Routine use of on-table cholangiography in
some trials influencing postoperative
morbidity and operation time.
Pre-incisional local infiltration and intraperitoneal local anaesthetic spray in some
trials influencing the duration and intensity of
postoperative pain.
Suppl. Figure 1: Strength and summary of the evidence analysed on GradePro®