Doctors say there may be a new way to diagnose depression.

Your blood can help doctors detect cholesterol, cancer and even infectious diseases. Now, blood is being used to figure out what’s going on inside your head, too.

Statistics show depression affects 15 million Americans and impacts women twice as much as men.

Angel Schwiefert was diagnosed with depression, also known as major depressive disorder, a few years ago.

She tried three different anti-depressants. 

"We really couldn’t get the dosages right or the right medications,” said Schwiefert.

“I worry that these meds are thrown at folks," said Dr. James A. Smith III, medical director at Carolina Partners in Mental Health Care. 

The psychiatrist said diagnosing depression and getting patients the right treatment can mean a lot of trial and error. 

“Piecing it all together can be a bit of a challenge," he admitted.

Smith said blood work could take away some of the guess work.

MDD Score is the first blood test claiming to assist in the diagnosis of depression.

It measures nine biomarkers and ranks a person’s likelihood of having the condition from one to nine.

“I see it as extremely accurate," said Smith.

In studies funded by the test maker, MDD Score was more than 90 percent accurate.

Duke University psychiatrist Dr. Harold Koenig, however, has some concerns. 

“False positives and false negatives, people who are diagnosed with depression with this test who don’t have depression, or missing the depression potentially in someone who really has it who wouldn’t get the treatment," he explained.

Regardless, Angel scored high on the blood test. She said she was totally surprised.  Her psychiatrist then upped the dosage of her anti-depressant and said she's much better now.

Right now, MDD Score is available in most states. Company officials said it should be available nationwide by the end of the year.

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