Despite overwhelming scientific evidence that depression is, indeed, a disease, there remains a sometimes-vocal minority of critics who insist that the mood disorder was invented by pharmaceutical companies in order to sell drugs. While it is doubtful that these critics, like all conspiracy theorists, will ever become convinced by facts, a San Diego-based company, Ridge Diagnostics, is hopeful that a blood test that detects biomarkers for Major Depressive Disorder will convince more critics that there is something more than a psychiatrist's opinion involved in the diagnosis. "By having a biological indication of depression, patients and their families have a better understanding of the condition as a medical one, which reduces the stigma of mental health disorders and leads to an improvement in treatment compliance," Lonna J. Williams, Ridge's CEO, says in a release. The quotation comes from a larger article in Psychiatric Times, which outlines the search for blood tests for both depression and schizophrenia. Release | Article