The Ohio State University Wexner Medical Center is participating in one of the largest, worldwide studies on depression ever undertaken. Researchers are looking for new participants with symptoms of depression. Researchers hope to develop better ways to diagnose the disease and personalize treatment. The study is looking at genetic markers, brain structure and brain function in order to better diagnose and treat depression. Answers are needed because the use of antidepressants has skyrocketed in this country - up nearly 400% in just one generation. Doctors admit they can’t always predict what will work.