Glauser 2013a.

Study characteristics
Methods	Parallel, randomised, double‐blind study, with partial cross‐over to open‐label (at treatment failure only) with subsequent follow‐up. Follow‐up 12 months.
Participants	453 drug‐naive participants (193 male, 260 female), aged between 7 months to 12 years 11 months. All participants with typical AS.
Interventions	Monotherapy with LTG, VPS, or ESM.
Outcomes	Freedom from treatment failure assessed 12 months after randomisation.
Notes	This study was not sponsored by any commercial organisation.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Random sequence was generated using permuted blocks.
Allocation concealment (selection bias)	Low risk	Central allocation.
Blinding (performance bias and detection bias) All outcomes	Low risk	Placebo and active drugs indistinguishable.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Placebo and active drugs indistinguishable.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Placebo and active drugs indistinguishable.
Incomplete outcome data (attrition bias) All outcomes	Low risk	No missing outcome data.
Selective reporting (reporting bias)	Low risk	The study protocol is not available but it is clear that the published reports include all expected outcomes.

AS: absence seizure
EEG: electroencephalogram
ESM: ethosuximide
LTG: lamotrigine
PCB: placebo
VPA: valproic acid
VPS: sodium valproate