Placencia 1993

Methods	Randomised, parallel‐group trial conducted in the context of existing community health care in a rural highland area of a developing country (Ecuador) 2 treatment arms: CBZ and PHB
Participants	Participants with a history of at least 2 afebrile seizures and no previous AED treatment in the 4 weeks preceding the trial were eligible Number randomised: PHB = 97, CBZ = 95 67 male participants (35%) 133 participants with partial epilepsy (69%) Mean age (range): 29 (2‐68) years
Interventions	Monotherapy with PHB or CBZ Minimum maintenance doses by age groups: 2‐5 years: PHB: 15 mg/d, CBZ: 150 mg/d; 6‐0 years: PHB: 30 mg/d, CBZ: 300 mg/d; 11‐15 years: PHB: 45 mg/d, CBZ: 500 mg/d; > 16 years: PHB: 60 mg/d, CBZ: 600 mg/d. Doses gradually increased Doses achieved not stated
Outcomes	Proportion seizure‐free at 3‐, 6‐, and 12‐month follow‐ups Proportion seizure‐free, with more than 50% seizure reduction and no change in seizure frequency in 6‐ to 12‐month follow‐up period Incidence of adverse effects Trial duration: 12 months Range of follow‐up: 3.5‐23 months
Notes	We received IPD for all outcomes used in this review from the trial author. Results in the published paper were given for 139 participants who completed 6 months' follow‐up, but we received IPD for all 192 participants randomised
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Participants randomised with random number list, no information provided on method of generating random list
Allocation concealment (selection bias)	High risk	Allocation concealed using sealed, opaque envelopes but method not used for all participants (information provided by trial author)
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	No information provided
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	No information provided
Incomplete outcome data (attrition bias) All outcomes	Low risk	Attrition rates reported, all randomised participants analysed from IPD provided (see footnote 2)
Selective reporting (reporting bias)	Low risk	All outcomes were reported or calculated with the IPD provided (see footnote 2)
Other bias	High risk	Inconsistencies between number and reasons of withdrawals between the data and the published paper, which could not be resolved by the author