The DSM-5 (Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition) outlines the criteria for Major Depressive Disorder (MDD), commonly known as depression. For a diagnosis of MDD, at least five of the following symptoms must be present during the same two-week period, and at least one of the symptoms must be either a depressed mood or loss of interest or pleasure:

DSM-5 Criteria for Major Depressive Disorder:

1. Depressed mood most of the day, nearly every day, as indicated by subjective reports (e.g., feeling sad, empty) or observations made by others (e.g., appearing tearful). In children and adolescents, this may manifest as an irritable mood.
2. Markedly diminished interest or pleasure in all, or almost all, activities most of the day, nearly every day.
3. Significant weight loss when not dieting or weight gain (a change of more than 5% of body weight in a month), or a decrease or increase in appetite nearly every day. In children, this may manifest as failure to make expected weight gains.
4. Insomnia or hypersomnia nearly every day.
5. Psychomotor agitation or retardation nearly every day, observable by others (i.e., not merely subjective feelings of restlessness or being slowed down).
6. Fatigue or loss of energy nearly every day.
7. Feelings of worthlessness or excessive or inappropriate guilt (which may be delusional) nearly every day.
8. Diminished ability to think or concentrate, or indecisiveness, nearly every day.
9. Recurrent thoughts of death (not just fear of dying), recurrent suicidal ideation without a specific plan, or a suicide attempt or a specific plan for committing suicide.

Additional Criteria:

• Duration: The symptoms must persist for at least two weeks and represent a change from previous functioning.
• Impairment: The symptoms cause clinically significant distress or impairment in social, occupational, or other important areas of functioning.
• Exclusion: The episode is not attributable to the physiological effects of a substance (e.g., drug abuse, medication) or another medical condition.
• No history of manic or hypomanic episodes: The diagnosis of major depressive disorder excludes a history of manic or hypomanic episodes, as this would indicate a diagnosis of bipolar disorder.

DSM Cover image source:

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