Kaplan-Meier plot for total relapse-free-time by treatment cohort with change of treatment considered censored. All patients (N = 761). Definition of relapse: CGI-BP worsening of a minimum of 2 points, hospitalization due to psychiatric disease, and death related to bipolar disease were counted as an event (i.e. relapse). Patients who dropped out or died from other causes and patients who changed their mood stabilizing therapy were considered censored. Abbreviations: OM = Olanzapine monotherapy, LM = Lithium monotherapy, AM = Anticonvulsive monotherapy, OLC = Olanzapine/lithium combination therapy, OAC = Olanzapine/anticonvulsive combination therapy, OC = Other combinations of mood-stabilizers, OMS = Other mood stabilizing therapy.