Table 4.

Reasons for premature discontinuation (withdrawal of allocated treatment)

Reason for early termination	Classification	De Silva 19962		Heller 19952,3		Ramsey 1992		Turnbull 1985		Total1
		PHT n = 53	SV n = 47	PHT n = 63	SV n = 58	PHT n = 50	SV n = 86	PHT n = 70	SV n = 70	PHT n = 236	SV n = 261
Adverse events/intoxication	Event	2	2	1	4	5	7	14	7	22	20
Poor seizure control/lack of efficacy	Event	10	11	8	9	2	1	0	2	20	23
Both adverse events and lack of efficacy	Event	5	4	2	6	0	0	2	1	9	11
Non‐compliance	Event	0	0	0	0	1	7	2	2	3	9
Participant went into remission	Censored	24	16	14	13	0	0	0	0	38	29
Lost to follow‐up	Censored	0	0	0	0	4	10	7	7	11	17
Death4	Censored	0	0	0	0	0	0	3	3	3	3
Other5	Censored	0	0	0	0	2	1	0	0	2	1
Completed the study/did not withdraw	Censored	12	14	38	26	36	60	42	48	128	148

n = number of individuals contributing to the outcome 'Time to withdrawal of allocated treatment'; PHT: phenytoin; SV: sodium valproate ¹IPD for 'Time to withdrawal of allocated treatment' was not provided for Craig 1994. ²Three participants for Heller 1995 (all SV) and three for De Silva 1996 (one PHT and two SV) have missing reasons for treatment withdrawal. ³Four participants from Heller 1995 had missing withdrawal times and did not contribute to analysis but reasons for withdrawal are given. ⁴Death due to reasons not related to the study drug. ⁵Other reasons from Ramsay 1992 – two participants withdrew due to pregnancy and one for personal reasons.