Assertion: depression's episode | /r/HasProperty | unnecessary
Facets:
value: for the diagnosis
type: PURPOSE
Source sentences:
text: I disorder: At least one manic episode is necessary to make the diagnosis;  depressive episodes are common in the vast majority of cases with bipolar disorder I, but are unnecessary for the diagnosis.  
text: depressive episodes are common in the vast majority of cases with bipolar disorder I, but are unnecessary for the diagnosis.