Eleven RCTs with a total of 1,722 participants were included. The analyses were based on 10 RCTs with a total of 1,527 participants.
Intermittent diazepam versus placebo (4 RCTs).
In the diazepam group, 11.2% (44 out of 393) had a recurrence of febrile convulsion compared with 17.1% in the placebo group (68 out of 398); the OR was 0.6 (95% CI: 0.40, 0.90) in favour of treatment with diazepam. The NNT was 17 (95% CI: 10, 85). Significant statistical heterogeneity was observed in the trials (chi-squared 10.19, P<0.01).
Phenobarbital versus placebo (6 RCTs).
In the phenobarbital group, 24.5% (71 out of 290) experienced a recurrence of febrile convulsion compared with 37.0% (114 out of 308) of the placebo group; the OR was 0.54 (95% CI: 0.38, 0.76) in favour of treatment with phenobarbital. The NNT was 8 (95% CI: 5, 18). Significant statistical heterogeneity was observed in the trials (chi-squared 15.40, P<0.01).
Intermittent diazepam or phenobarbital versus placebo (10 RCTs).
The OR for recurrence of febrile convulsion with either intermittent diazepam or phenobarbital versus placebo was 0.56 (95% CI: 0.43, 0.73) in favour of active treatment. The NNT was 12 (95% CI: 8, 22). Significant statistical heterogeneity was observed across the trials (chi-squared 25.76, P=0.0022).