Huang 2009

Methods	Randomised, parallel group unblinded study. Follow‐up 12 months.
Participants	48 drug naive participants, all with typical absence seizures, age 6 to 10 years
Interventions	Monotherapy with VPS or LTG.
Outcomes	Seizure freedom at 1, 3, 6 and 12 months. Complete normalisation of EEG with seizure freedom.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Insufficient information to permit judgement.
Allocation concealment (selection bias)	Unclear risk	Insufficient information to permit judgement.
Blinding (performance bias and detection bias) All outcomes	High risk	No blinding.
Blinding of participants and personnel (performance bias) All outcomes	High risk	No blinding.
Blinding of outcome assessment (detection bias) All outcomes	High risk	No blinding.
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.