Diagnostic Criteria for Bipolar II Disorder

Key Diagnostic Features

• The World Health Organization's ICD-11 requires increased activity or energy in addition to mood elevation or irritability for diagnosing hypomania, and maintains the 4-day minimum duration for hypomanic episodes, with a focus on dimensional symptom assessment and severity ratings 1, 2
• The American Psychiatric Association's DSM-5-TR and ICD-11 both recognize Bipolar II disorder as a distinct diagnostic category, with a requirement for at least one hypomanic episode and one major depressive episode, and no history of mania, although ICD-11 allows for more nuanced characterization of depressive episodes 1, 2

Diagnostic Challenges and Controversies

• ICD-11 field studies showed promising but modest improvements in diagnostic accuracy compared to ICD-10, with 82.5% to 83.9% of clinicians rating ICD-11 as quite or extremely easy to use, highlighting the need for ongoing evaluation and refinement of diagnostic criteria 1, 2