The present analysis of a large and unselected nationwide population provides important complementary data to that from controlled trials. Although various mechanisms may be responsible for the results, the data support the utilization of lithium or valproate, rather than SGAs, as the initial antimanic treatment in bipolar disorder. A large-scale, prospective, randomized, pragmatic clinical trial comparing the initiation of SGA monotherapy to that of lithium or valproate monotherapy is a logical next step.