Jain 1978a.

Study characteristics
Methods	RCT
Participants	Setting: Department of Medicine, Tulane University School of Medicine, New Orleans, Louisiana, USA (assumed from author affiliation) Trial dates: not reported (published in 1978) Inclusion criteria: women with moderate to severe episiotomy pain within 48 hours of a normal vaginal birth Exclusion criteria: nursing; systemic diseases; allergic to aspirin
Interventions	Aspirin (N = 30 randomised) 648 mg aspirin; single oral dose Placebo (N = 30 randomised) Placebo; single oral dose All women: the time between the test drug and previous analgesic, tranquillisers, or sedatives was at least 5 hours
Outcomes	Adequate pain relief as reported by the woman: a trained nurse observer rated pain intensity and relief hourly for 4 hours Observer rating of pain intensity on 4‐point scale (0 = none; 1 = slight; 2 = moderate; 3 = severe) Observer rating of pain relief on 5‐point scale (0 = none; 1 = slight 2 = moderate; 3 = marked; 4 = complete) Patient self‐rating of pain from 0 to 1 on a continuous scale (no pain to severe pain) The results were not reported in a way to enable us to calculate 'Adequate pain relief as reported by the woman.' Figure 2 in manuscript provides patient self‐rating of pain (continuous, analogue scale) Need for additional pain relief in the first 48 hours for perineal pain: need for extra analgesia during the 4‐hour study period Maternal adverse effects: volunteered or observed side effects
Notes	Funding: not reported Declarations of interests: not reported Additional arms: this 4‐arm trial also assessed piroxicam 20 mg (N = 31) and 40 mg (N = 29); we only included the relevant arms in this review
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "By random assignment"; no other details described
Allocation concealment (selection bias)	Unclear risk	No details provided
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Quote: "double blind"; no further details provided
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	No details provided
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Did not report on losses to follow‐up or exclusions
Selective reporting (reporting bias)	High risk	No access to trial protocol; however results reported incompletely in text
Other bias	Low risk	Baseline characteristics were reported to be comparable across groups; no other obvious sources of bias identified