Privitera 1996.

Methods	Double‐blind, parallel‐group study 4 treatment arms: 1 placebo, 3 topiramate Pre‐randomisation baseline period: 12 weeks Treatment period: 18 weeks
Participants	A multicentre study (USA) 190 people were randomised (all with drug‐resistant focal epilepsy): 47 to placebo, 48 to 600 mg topiramate, 48 to 800 mg topiramate, 47 to 1000 mg topiramate Age range: 18 to 68 years Mean age: 35.5 years 80% males Other AEDs: 2 or fewer Median baseline monthly seizure frequency: 11 (9.3 for placebo group, 10.0 for 600 mg/d topiramate group, 16.2 for 800 mg/d topiramate group, 11.7 for 1000 mg/d topiramate group)
Interventions	600 mg topiramate per day or 800 mg topiramate per day or 1000 mg topiramate per day or placebo
Outcomes	Percentage seizure rate reduction Percentage responders (≥ 50%) Adverse effects
Notes	Trial sponsored by Johnson & Johnson
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Comment: random permuted blocks
Allocation concealment (selection bias)	Low risk	Comment: sealed, numbered packages allocated sequentially
Blinding (performance bias and detection bias) All outcomes	Low risk	Quote: "topiramate and placebo tablets were identical in appearance and packaging"
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Comment: it is likely that blinding was maintained
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Comment: specific details of outcome assessment blinding not provided
Incomplete outcome data (attrition bias) All outcomes	Low risk	Quote: "all 209 subjects who enrolled in the double‐blind phase of the trial were included in the efficacy analysis"
Selective reporting (reporting bias)	Low risk	Comment: data published in full according to the protocol
Other bias	Low risk	Comment: the study appears to be free of other sources of bias