The heterogeneous nature of depression
Depression is often viewed as a common medical disorder like measles -- one either has it or one doesn't. As a result, diagnosis is generally followed by assigning specific treatment options. But unlike physical disorders where blood tests or other objective tests enable a reliable diagnosis, there are no such measures to determine whether someone is depressed. Instead, researchers and clinicians query patients about symptoms that are indicative of depression, such as sadness, suicidal ideation and sleep problems. If a person has many depression symptoms, she is considered depressed. Heterogeneity In his study, Fried used a content analysis to investigate the symptom overlap of 7 rating scales of symptoms that are commonly used in depression research. One of the scales is the Hamilton Rating Scale of Depression, which contains 17 predominantly physical depression symptoms like paralysis, weight loss and psychomotor retardation. Another is the Beck Depression Inventory, which...