Valenzuela 2009.

Methods	RCT. Individual randomisation.
Participants	Setting: The Hospital Universitario Principe de Asturias (state hospital), Madrid. Recruitment period: September 2005 to July 2007. Ethics committee approval obtained. 445 women with an episiotomy or second‐degree tear. Method of delivery: ? spontaneous vaginal birth. Parity: ? primigravidae and multigravidae. Mean age: group 1 = 30.2 years; group 2 = 30.1 years. Operator: ? 4 midwives with more than 5 years' experience of attending deliveries and trained in both suturing techniques. Inclusion criteria: vaginal childbirth; viable foetus at least 37 weeks' gestation; delivered by 1 of the 4 matrons participating in the research; episiotomy or second‐degree tear affecting the skin and muscle. Exclusion criteria: instrumental delivery; episiotomy or perineal tear involving the anal sphincter or rectum; baby born with serious congenital malformations.
Interventions	Method of repair: described as below. Women divided into 2 groups. Group 1 (N = 222) continuous non‐locking sutures in the vagina, perineum and subcutaneous tissue using Polyglactin 910 (Vicryl Rapide) on a 36‐mm needle, calibre/gauge 0. Group 2 (N = 223) vaginal trauma repaired with a continuous locking suture; interrupted sutures in the perineal muscle and interrupted transcutaneous sutures to close the skin using Polyglactin 910 (Vicryl Rapide) on a 36‐mm needle, calibre/gauge 0.
Outcomes	Included in analysis: short‐term pain (pain now) at day 2 and 10; pain when moving, sitting, passing urine, opening bowels at 2 and 10 days; use of painkillers (analgesia) analgesia at 2 and 10 days' and 3 months' postpartum; long‐term pain at 3 months; dyspareunia at 3 months; re‐suturing; removal of suture material; number of packets of suture material used; time taken to complete the repair.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer generated.
Allocation concealment (selection bias)	Low risk	Numbered opaque envelopes.
Blinding (performance bias and detection bias) Clinical staff	High risk	Different techniques used.
Blinding (performance bias and detection bias) Women	High risk
Blinding (performance bias and detection bias) Outcome assessors	Low risk	"The midwife who conducted the questioning did not know the technique that had been used and was also blinded to other patient data".
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	445 women randomised and primary analysis was by ITT. High response rate at 2 and 10 days and at 3 months (3.6% in the continuous group and 6.7% in the interrupted group were lost to follow‐up at 3 months' postpartum).
Other bias	Unclear risk	All women received intervention as allocated. No baseline imbalance apparent.