The economic downturn is not only depressing the economy, but also the public. According to the World Health Organization, depression is twice as common among the poor as among the rich, and recent U.S. census figures indicate that more than 26 million Americans are now living in poverty.

About half of American adults will develop a mental illness in their lifetime, according to the Centers for Disease Control and Prevention. To help combat this, organizations are encouraging participation in National Depression Screening Day—held Oct. 6—which serves as a "supportive community initiative to connect the public with mental health screenings."

"We know unemployment and financial problems can take a toll on an individual's mental health, which is why we're encouraging the public to take easy, anonymous screening to help those who may be struggling," says Douglas Jacobs, associate clinical professor of psychiatry at Harvard Medical School and the founder of Screening for Mental Health.