Roberts 1983.

Methods	RCT.
Participants	Setting ‐ Stobhill General Hospital, Glasgow, UK. 190 women randomised. Inclusion criteria ‐ all women who had either a spontaneous vaginal delivery or forceps with an episiotomy. Exclusion criteria ‐ no details given. Parity ‐ not stated.. Mean age ‐ not specified. Operator ‐ not clear.
Interventions	Method of repair ‐ continuous suture to close vaginal epithelium and interrupted sutures for muscle layers and skin (buried knots). Intervention group (n = 88) vagina and muscle sutured with polyglycolic acid (Dexon gauge1‐0) and skin sutured with polyglycolic acid (Dexon gauge2‐0) using an interrupted technique and buried knots. Comparison group (n = 84) vagina and muscle sutured with chromic catgut (gauge1‐0) and skin sutured with plain catgut (gauge 2‐0) using an interrupted technique and buried knots.
Outcomes	Short‐term pain on rest ‐ 1 to 10 days. Short‐term pain on movement ‐ 1 to 10 days. Analgesia ‐ up to day 5. Bruising ‐ day 2 and 4. Oedema ‐ day 2 and 4.
Notes	Not clear if all repairs were carried out by a single investigator. Patients were assessed daily for 5 days after delivery by the obstetrician. Assessed at home on tenth day by district midwife.
Risk of bias
Bias	Authors' judgement	Support for judgement
Adequate sequence generation?	Unclear risk	Allocated by a "randomisation schedule".
Allocation concealment?	Unclear risk	No information available regarding concealment of treatment allocation.
Blinding? Women	Unclear risk	Described as "double‐blind trial".
Blinding? Clinical staff	Unclear risk	This would be difficult due to differences in suture materials
Blinding? Outcome assessors	Unclear risk	This would be difficult due to differences in suture materials.
Incomplete outcome data addressed? All outcomes	Unclear risk	18 of 190 women randomised were excluded from the analysis because 'they were unable to complete the study due to being discharged early or tablets were lost'. Authors state that loss was balanced across groups.
Free of other bias?	Unclear risk	Women in the 2 study groups were described as having similar characteristics.