Mehlisch 1995.

Methods	Randomised, parallel group, double blind study
Participants	240 participants randomised to 3 groups, 1 withdrawal from the acetaminophen group Number randomised to intervention (1 withdrawal): male 30, female 71, mean age 25.3, age range 15‐60 Number of third molars removed/patient: (1/0, 2/95, 3/3, 4/3) Number randomised to placebo: male 19, female 21, mean age 24.2, age range 15‐48 Number of third molars removed/patient: (1/0, 2/39, 3/0, 4/1) Baseline pain intensity: mean for intervention 2.21 (moderate 80, severe 21), mean for placebo 2.20 (moderate 32, severe 8) Setting not stated (USA)
Interventions	Paracetamol 1000 mg versus placebo Formulation: 2 tablets Anaesthesia: not stated
Outcomes	PI at 4 hours and 6 hours, categorical scale 0‐3 (none ‐ severe) PR at 4 hours and 6 hours, categorical scale 0‐4 (none ‐ complete) Global assessment: categorical scale 0‐4 (poor ‐ excellent) Adverse events reported by number of patients
Notes	Sponsored by Biomedical Research Group; and Merck Research Laboratories
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment (selection bias)	Low risk	A ‐ Adequate