Briefly stated it is an ICD not DSM term. The significant difference is that in schizophrenia, psychosis (the presence of delusions and hallucinations) is usually present, but there is not necessarily a change in mood. In an effective psychosis there are the same psychotic symptoms but there is also a prominent disturbance in mood usually severely depressed, but can also be an unrealistic euphoria. So to recap: In schizophrenia the psychosis is prominent and there may or may not be mood disturbances. Whereas is in an Affective Psychosis, the prominent feature is the the severe disturbance of mood-usually depression, with the psychosis be present, but secondary. I hope that this has been helpful and I wish you the best.
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