Alvandipour 2016.

Study characteristics
Methods	Design: parallel‐group RCT Study period: February 2015–May 2015
Participants	Setting: elective general or colorectal surgery Type of stoma: ileostomy Inclusion criteria Age ≥ 18 years Colorectal cancer Protective ileostomy after surgery Benign condition that required ileostomy Exclusion criteria Death or dropout Need for secondary surgery at other centres
Interventions	PSSC using subcuticular absorbable suture (n = 34) versus LSC using interrupted non‐absorbable suture (n = 32). No mesh or drain was used during closure in either group.
Outcomes	SSI (any infection of the superficial or deep tissues or the organ/space affected by the surgery when no prosthesis has been implanted) as identified by a surgeon in the outpatient clinic within 30 days of surgery Operating time Length of hospital stay Postoperative pain (VAS) at 3 days, 7 days, 1 month, and 3 months after surgery Participant satisfaction with the wound or scar (VAS) at 3 days, 7 days, 1 month, and 3 months after surgery
Notes	The 2 groups were comparable in terms of baseline demographics (age, sex, BMI) and comorbidities. The length of follow‐up was 3 months. The study received no external funding, and the protocol had been registered with the Iranian Registry of Clinical Trials (registration number: IRCT2015040714483N3). The study authors declared no conflicts of interest.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Article describes method of randomisation but not type of randomisation.
Allocation concealment (selection bias)	High risk	Method used for randomisation is not recognised to support allocation concealment.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Participants and personnel were not blinded (blinding may not be practical in this setting).
Blinding of outcome assessment (detection bias) All outcomes	High risk	Outcome assessment was not blinded (blinding may not be practical in this setting).
Incomplete outcome data (attrition bias) All outcomes	Low risk	Complete outcome data for all participants.
Selective reporting (reporting bias)	Low risk	No selective reporting detected.
Other bias	Low risk	No other sources of bias detected.