chotic and mood symptoms, and thus psychoti c disorder due to another medical condition
needs to be excluded. Distinguishing schizoaffective disorder from schizophrenia and
from depressive and bipolar diso rders with psychotic features  is often difficult. Criterion
C is designed to separate schizoaffective di sorder from schizophrenia, and Criterion B is
designed to distinguish schizoaffective diso rder from a depressive or bipolar disorder
with psychotic features. More specifically, schizoaffective disorder can be distinguished
from a depressive or bipolar disorder with psyc hotic features due to the presence of prom-
inent delusions and/or hallucinations for at least 2 weeks in the absence of a major mood
episode. In contrast, in depressive or bipo lar disorders with psychotic features, the psy-
chotic features primarily occur during the mo od episode(s). Because the relative propor-
tion of mood to psychotic symptoms may ch ange over time, the appropriate diagnosis
may change from and to schizoaffective disord er (e.g., a diagnosis of schizoaffective dis-
order for a severe and prominent major depre ssive episode lasting 3 months during the
first 6 months of a persistent psychotic illnes s would be changed to schizophrenia if active
psychotic or prominent residual symptoms pe rsist over several years without a recurrence
of another mood episode).
Psychotic disorder due to another medical condition. Other medical conditions and
substance use can manifest with a combinat ion of psychotic and mood symptoms, and
thus psychotic disorder due to another medical condition needs to be excluded. 
Schizophrenia, bipolar, and depressive disorders. Distinguishing schizoaffective dis-
order from schizophrenia and from depressiv e and bipolar disorders with psychotic fea-
tures is often difficult. Criterion C is design ed to separate schizoaffective disorder from