-- Question: How is depression diagnosed?
Answer: Depression is typically diagnosed simply by a clinical interview with the patient, so talking with the patient and asking about the core depressive symptoms.
And key symptoms of depression include sad mood, lack of interest in things, disruption in sleep, disruptions in appetite, low energy, difficulties with concentration, feelings of worthlessness or shame or guilt, thoughts about death or suicide, and also feeling either agitated or slowed down. So when meeting with the patient we'll ask them about symptoms like this, and that's the primary way we diagnose depression.
Sometimes there are questionnaires or rating scales that we can use. These are a series of questions that we would ask to the patients about these symptoms. And those can be helpful in terms of gauging the severity of the depression, identifying what symptoms are most problematic, and it can also be helpful for tracking the depression over time so that as the patient continues in treatment, you can do these rating scales many times, and that way you can track how well they're responding to treatments.