Laska 1981 Study 1.

Study characteristics
Methods	Randomised controlled trial
Participants	Setting: multicentre study; Hospital Maternidad ‐ Concepcion Palacios and University Hospital in Caracas Venezuela. Time not given Inclusion criteria: postpartum women who had a vaginal birth with severe postpartum uterine cramp pain; gave consent and had no complicating illness, and were expected to tolerate the medication well Exclusion criteria: women breastfeeding, with complicating illness and expected not to tolerate the medication well
Interventions	Following initial pain assessment by a trained nurse observer women were randomly allocated to 1 of 6 treatment groups and given 1 of 6 study preparations: Fenoprofen 50 mg (N = 28) Fenoprofen 100 mg (N = 29) Fenoprofen 200 mg (N = 29) Fenoprofen 300 mg (N = 29) Codeine phospate 60 mg (N = 29) Placebo (N = 28)
Outcomes	Adequate pain relief as assessed by the woman: pain intensity was assessed at baseline and 1, 2, 3, 4 and 5 hours post‐study medication Pain was assessed using a 4‐point ordinal scale, no pain (0), slight pain (1), moderate pain (2), severe pain (3). Pain intensity difference was calculated. SPID scores were used to calculate 'adequate pain relief as assessed by the woman (estimated over 5 hours)
Notes	Primary objective of this study was to assess the dose‐response of fenoprofen Some women who delivered by caesarean were randomised into the study but excluded from the analyses, 'N' above exclude these women Dates of study: not stated Funding sources: not stated Declarations of interest: none
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Women were "assigned according to a random code"
Allocation concealment (selection bias)	Unclear risk	Insufficient information to make this judgement
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Study was double‐blind. Study medications were "identical in appearance". "Neither the patient or the observer knew which medication was being given"
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Study was double‐blind. Study medications were "identical in appearance". "Neither the patient or the observer knew which medication was being given."
Incomplete outcome data (attrition bias) All outcomes	High risk	37 women were randomised into the study who had delivered by caesarean, but were not included in the analysis. There were 28 women allocated to the fenoprofen 50 mg and placebo groups, the remaining 4 groups had 29 women each. Table 1 reports the number of women in each study group, results tables do not provide the number of women included in each study group. It is unclear at which point the women who birthed by caesarean were excluded and if any women withdrew during the first 2 hours of the study. Women who withdrew before the second hour for additional analgesia were withdrawn from the study. For women who withdrew after the second hour to receive additional pain relief, their responses to the last observation were assumed for the duration of the experiment
Selective reporting (reporting bias)	Unclear risk	No published protocol or trial registration available
Other bias	Unclear risk	Women who gave birth by caesarean were randomised but excluded from the analyses. Unclear if randomisation was stratified by source of pain; uterine cramp or episiotomy although data analysed separately