Ogunrin 2005

Methods	Double‐blinded, parallel group, randomised study conducted in a single‐centre in Nigeria. 3 treatment arms: carbamazepine, phenytoin, phenobarbitone
Participants	Consectuive newly diagnosed participants aged 14 or over presenting at the outpatient neurology clinic of the University Teaching Hopsital, Benin City, Nigeria, with recurrent, untreated afebrile seizures Number randomised: PB = 18, CBZ = 19 7 participants with partial seizures (19%) 22 male participants (59%) Mean age (range): 23.62 years (14 to 38 years) Range of follow‐up: all participants followed up for 12 weeks
Interventions	Monotherapy with PB or CBZ. Median daily dose (range): PB = 120 mg (60 to 180 mg), CBZ = 600 mg (400 mg to 1200 mg)
Outcomes	Cognitive measures (reaction times, mental speed, memory, attention)
Notes	We received IPD for all randomised participants. The study duration was 12 weeks; all participants completed the study without withdrawing; therefore, we could not calculate the outcomes 'time to withdrawal of allocated drug', 'time to six‐month remission', and 'time to 12‐month remission'. We calculated 'time to first seizure' from the IPD provided
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	The study randomised participants using simple randomisation: Each participant was asked to pick 1 from a table of numbers (1 to 60); the numbers corresponded to allocation of 1 of 3 drugs (the author provided information).
Allocation concealment (selection bias)	Low risk	Recruitment/randomisation of participants and allocations of treatments took place on different sites (the author provided information).
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Participants were single‐blinded. The study did not blind the research assistant recruiting participants and counselling on medication adherence.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Investigators performing cognitive assessments were single‐blinded.
Incomplete outcome data (attrition bias) All outcomes	Low risk	All randomised participants completed the study. We analysed all randomised participants from the IPD provided².
Selective reporting (reporting bias)	Low risk	We calculated 1 outcome for this review from the IPD provided². Other outcomes for this review were not available because of short study length. All cognitive outcomes from the study were well reported.
Other bias	Low risk	We detected no other bias.