There are a number of articles floating around the web these days about the possibility of genetic and blood tests for depression. They tend to address how these tests could improve the diagnosis of depression. This approach confuses me a little bit because diagnosis has traditionally been based on the person’s personal experience and symptoms. This approach of biologically testing for depression seems like it could exclude people who are experiencing depression symptoms from a Major Depressive Disorder diagnosis.
I have been an opponent of the traditional approach to diagnosis since I began my studies in psychology. One of the major objections against mental disorder diagnosis in its current form is that the line between who does meet sufficient criteria and who does not is somewhat arbitrary—as if depression is an either/or condition, versus occurring across a continuum.
I am truly hoping that with these emerging tests we can identify forms of depression that respond particularly well to particular medications. But I hope that we do discount or dismiss people who sincerely experience symptoms of depression because they do not have the right chemicals in their blood. Depression is as much a human experience (with probably a variety of causes) as it is a chemical condition. If “depression screening” becomes “depression testing” we risk leaving a lot of people out of treatment.