>>"We know that depression is very heterogenous, and that there are at least 1,000 unique combinations of symptoms that can be diagnosed as depression," said Williams, who is the director of Stanford's Center for Precision Mental Health and Wellness. "We've found that brainwave measurements can be used to help identify which particular symptoms change with antidepressant treatment and which do not."

They're not claiming to detect depression, I don't think there is "sorts" of depression. They're measuring a change in symptoms to evaluate a medicines usefulness.

The headline is misleading but I do feel their work has merit. Years ago I had an isolated Major Depressive Episode. It's clear to me that during that period of time there was something different about my brain.