Which statement accurately describes Bipolar I and Bipolar II?

• A. Bipolar I includes hypomanic episodes only; Bipolar II includes manic episodes
• B. Bipolar I includes manic episodes; Bipolar II includes hypomanic episodes
• C. Both disorders require manic episodes
• D. Hypomanic episodes are not part of any bipolar disorder

Answer: (B)

This item tests how manic and hypomanic episodes map onto the bipolar diagnoses. A manic episode is the defining feature of Bipolar I; it involves a period of abnormally elevated, expansive, or irritable mood with increased energy that lasts at least a week (or is severe enough to require hospitalization) and causes marked impairment. Bipolar II, on the other hand, is defined by the presence of at least one hypomanic episode—a milder form of mania that lasts at least four days and is noticeable to others but does not cause the same level of impairment or require hospitalization—along with at least one major depressive episode. Hypomania is therefore a hallmark of Bipolar II, not Bipolar I.

Why the other statements don’t fit: one option swaps manic and hypomanic features, which misstates the core diagnostic distinction; another claims both disorders require manic episodes, which ignores the defining hypomanic component of Bipolar II; and another denies hypomania in bipolar disorders, which contradicts Bipolar II’s criteria.