Are you depressed? (I was.) June 2, 2016 Leslie McClure, PhD, MS, professor and chair of the Department of Epidemiology and Biostatistics, authors a blog post on Philly.com's The Public's Health blog about major depression, noting that one in five American adults experience mental illness. One in five children ages 13-18 have, or will have, a serious mental illness. Sixteen million American adults live with major depression. View Story