Derzie 2000.

Methods	RCT Methods to control for contributory patient factors: none described
Participants	Age: no information provided Gender: no information provided Types of incisions: no information provided Type of surgery: Group 1: Roux‐en‐Y gastric bypass 83.1%, vertical banded gastroplasty 2.3%, revision procedures 14.5%, additional cholecystectomy 14.0% Group 2: Roux‐en‐Y gastric bypass 84.3%, vertical banded gastroplasty 6.9%, revision procedures 8.8%, additional cholecystectomy 13.8% Contamination classification of included participants: no information provided Preoperative antibiotic use: all participants received either cefazolin or gentamicin and vancomycin (if allergic to penicillins) Prognostic patient factors: all participants were morbidly obese Inclusion criteria: none described Exclusion criteria: none described
Interventions	Comparisons reported: Group 1: Sutures: nylon (in first 196 participants randomised), PDS (in the last 135 participants randomised) Suturing technique: continuous Closure method: mass Group 2: Sutures: nylon (in first 196 participants), PDS (in the last 135 participants) Suturing technique: interrupted, "figure‐of‐8" Closure method: mass Surgeon characteristics: no information provided
Outcomes	Incisional hernia: not measured Wound infection: local or systemic inflammation and collection of purulent subcutaneous fluid from wound Deep wound complications: included deep surgical site infections and fascial dehiscence
Notes	Follow‐up duration: "All wounds were monitored for 30 postoperative days." Dehiscence (n = 2) were not separated from "wound complications". All "wound complications" analysed as wound infection
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	"All patients were randomised by odd or even medical record number at the time of fascial closure to either continuous or interrupted fascial closure."
Allocation concealment (selection bias)	Unclear risk	Not described
Blinding (performance bias and detection bias) All outcomes	Unclear risk	Not described
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Not clearly reported
Selective reporting (reporting bias)	Low risk	There was no evidence of selective reporting
Other bias	Low risk	The study appears to be free of other sources of bias