Lithium vs valproate in the maintenance treatment of bipolar I disorder: A post- hoc analysis of a randomized double-blind placebo-controlled trial.

Overall, this study did not find significant differences in efficacy between the two mood-stabilizing agents when used as monotherapy or in combination with atypical antipsychotics. However, study design and small sample size might have precluded from detecting an effect if true difference in efficacy existed. Further head-to-head investigations with stratified designs are needed to evaluate maintenance therapies.