Joe Herbert, right, Emeritus Professor of Neuroscience at the University of Cambridge and Barbara Sahakian, left, professor of Clinical Neurophychology at the same university, pose for the photographer prior to a news conference to announce the results of a new study in central London, Monday, Feb. 17, 2014. A saliva test for teenage boys with mild symptoms of depression could help predict those who will later develop major depression, the new study says. Researchers who measured cortisol levels in teenagers found that boys with high levels of the hormone and mild depression symptoms were 14 times more likely to later suffer from clinical depression than those with low levels. Herbert said: "You don’t have to rely simply on what the patient tells you, but what you can measure inside the patient," comparing the new test to those done for other health problems, like heart disease, which evaluate things like cholesterol and high blood sugar to determine a patient’s risk. (AP Photo/Lefteris Pitarakis)LONDON (AP) — A saliva test for teenage boys with delicate symptoms of despair might assist determine folks who will later enhance major melancholy, a brand new study says.