Livingstone 1974.

Methods	Quasi‐randomised trial.
Participants	Setting ‐ Queen Mother's Hospital, Glasgow. 100 women randomised. Inclusion criteria ‐ first‐time mothers having spontaneous vaginal, rotation forceps, forceps or ventouse with a medio‐lateral episiotomy. Exclusion criteria ‐ women with additional lacerations or extended episiotomy. Parity ‐ primigravidae. Mean age ‐ not specified. Operators ‐ not specified.
Interventions	Method of repair ‐ standard continuous suture of vaginal epithelium and interrupted sutures for muscle layers and skin (for purpose of comparison similar gauge of suture material and size of needle was used). Intervention group (n = 50) sutured with polyglycolic acid No. 1 on a 40mm round bodied needle (vaginal and muscle) and No. 0 polyglycolic acid on a 37 mm diamond taper needle (skin). Comparison group (n = 50) sutured with plain catgut No. 1 on a 40 mm round bodied needle (vaginal and muscle) and No. 0 plain catgut on a 35 mm tapercut needle (skin).
Outcomes	Short‐term pain ‐ day 3. Suture dehiscence ‐ day 3 (introital dehiscence and total superficial dehiscence). Ease of movement ‐ day 3. Oedema ‐ day 3.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Adequate sequence generation?	Unclear risk	Allocated by quasi‐randomisation ‐ 'treatment allocation was determined on a random basis by drawing lottery cards'.
Allocation concealment?	Unclear risk	No information available regarding concealment of treatment allocation.
Blinding? Women	Unclear risk	Not stated.
Blinding? Clinical staff	Unclear risk	Described as "double blind" but not convinced that blinding was possible due to obvious differences in suture materials.
Blinding? Outcome assessors	Unclear risk	Researchers stated that by day 3 catgut had lost its distinguishing colour and was identical in appearance to Dexon, thus allowing the assessment to be described as 'double‐blind'. However, this is not convincing because interrupted sutures were used to appose the perineal skin and any differences in the suture material would be obvious.
Incomplete outcome data addressed? All outcomes	Unclear risk	All participants entered into the trial were included in the analysis but it was not clear whether analysis was by 'intention to treat'.
Free of other bias?	Low risk	No other bias apparent.