New research suggests that a blood test might help, although depression may be a difficult condition to diagnose correctly.

It is not clear the evaluation might cost, also it needs more stringent validation before it will be prepared to be found in medical offices. Nevertheless, “it seems these results are promising, after decades of research into locating a biological test for melancholy,” said study author Dr. George Papakostas, an associate professor of psychiatry at Harvard Medical School.

The research was funded by the Ridge Diagnostics Co. and appeared in a recent issue of the journal Molecular Psychiatry.

It does not desire a test to verify that it exists and may seem like depression is an easy condition to diagnose, but Papakostas said there are several ways that a blood-established depression test might be helpful.

For one, he said, a test could help physicians that aren’t as experienced in psychiatric ailments. Additionally, he explained, a test may provide support to doctors that aren’t confident about the appropriate analysis of a patient: “This could be of help to them, in terms of directing them in one way or another,” he said.

Another use for a test should be to check that a patient has depression, and for that reason help her or him accept the identification. “The majority of patients diagnosed with depression don’t have any problem accepting the importance of treatment,” Papakostas said. Yet, “there is a minority of patients who believe that validation of an inherent process is useful,” he added.

Within their study, his team and Papakostas gave a blood test to 36 patients with depression and 43 people who were not depressed. The test looked for amounts of nine different “biomarkers” in the blood which are associated with melancholy. These biomarkers are linked to interactions between brain structures related to other functions and the pressure response, the growth and upkeep of brain cells, and inflammatory processes.

The researchers found that the test correctly identified patients with depression 91 percent of the time; the remainder of the time it gave a false negative identification (it failed to spot the depression). The test accurately identified patients who were not depressed about 81 percent of the time, giving false positives the remainder of the time.

The next thing to do will be to try and validate these findings through further research, Papakostas said.

He said it should be more similar to routine blood tests and won’t be as high as thousands of dollars, although he didn’t know how much the test might eventually cost.

The evaluation seems to find inflammation in the mind, which has been associated with depression, Papakostas said. “That actually does not surprise research workers. Chronic inflammation was tied to numerous other sicknesses in the kidneys, lungs and heart,” he noted.

One outside expert said such a test will be welcome.

Dr. Michelle Riba, a professor of psychiatry at the University of Michigan who is comfortable with the findings, said a blood test for depression could be helpful in several ways.

It could be useful to identify people, particularly kids and teenagers, that are prone to depression and try and prevent it, she said.

Also, she said, a test could help give penetration to doctors into how time is being worked over by depression treatments.