DSM-5 Major Depressive Disorder
2.1. Five or more of the following symptoms have been present during the same 2-week period and represent a change from previous functioning; at one of the symptoms is either (1) depressed mood or (2) loss of interest or pleasure.
2.1.1. Depressed mood most of the day, nearly every day, as indicated by either subjective report (e.g., feeling sad, blue, down in the dumps, or empty) or observation made by others (e.g., appears tearful or about to cry). (In children and adolescents, this may present as an irritable or cranky, rather than sad, mood.)
2.1.2. Markedly diminished interest or pleasure in all, or almost all, activities every day, such as no interest in hobbies, sports, or other things the person used to enjoy doing.
2.1.3. Significant weight loss when not dieting or weight gain (e.g., a change of more than 5 percent of body weight in a month), or decrease or increase in appetite nearly every day.
2.1.4. Insomnia (inability to get to sleep or difficulty staying asleep) or hypersomnia (sleeping too much) nearly every day
2.1.5. Psychomotor agitation (e.g., restlessness, inability to sit still, pacing, pulling at clothes or clothes) or retardation (e.g., slowed speech, movements, quiet talking) nearly every day
2.1.6. Fatigue, tiredness, or loss of energy nearly every day (e.g., even the smallest tasks, like dressing or washing, seem difficult to do and take longer than usual).
2.1.7. Feelings of worthlessness or excessive or inappropriate guilt nearly every day (e.g., ruminating over minor past failings).
2.1.8. Diminished ability to think or concentrate, or indecisiveness, nearly every day (e.g. appears easily distracted, complains of memory difficulties).
2.1.9. Recurrent thoughts of death (not just fear of dying), recurrent suicidal ideas without a specific plan, or a suicide attempt or a specific plan for committing suicide
2.1.10. Symptoms cause clinically significant distress or impairment in social, occupational/academic, or other important areas of functioning.
2.1.11. The episode is not attributable to the physiological effects of a substance or to another medical condition.