Coppola 2004

Methods	Randomised, parallel group unblinded study. Follow‐up for 12 months.
Participants	38 drug naive participants, all with typical absence seizures, age 3 to 13 years.
Interventions	Monotherapy with VPS or LTG.
Outcomes	Total seizures freedom defined by clinical reports, 24 hours EEG and hyperventilation test.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Random sequence was generated using a randomisation code.
Allocation concealment (selection bias)	Low risk	Central allocation.
Blinding (performance bias and detection bias) All outcomes	High risk	No blinding. It is not stated whether tables of VPA and LTG were indistinguishable.
Blinding of participants and personnel (performance bias) All outcomes	High risk	No blinding. It is not stated whether tables of VPA and LTG were indistinguishable.
Blinding of outcome assessment (detection bias) All outcomes	High risk	No blinding. It is not stated whether tables of VPA and LTG were 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.