Should Everyone Really Be Screened for Depression?

About a year ago, the US Preventive Services Task Force (USPSTF) recommended that all adults, including pregnant women and new mothers, as well as adolescents 12 and older be screened for depression at least once by their doctor. This sounds like a great idea on its face—depression is the leading cause of disability worldwide and increased screening means more people can get help if they need it—but experts worried at the time that it would lead to overtreatment. (Health experts in the UK and Canada actually recommend against routine mental health screening.) Now, a new report in the journal BMJ doubles down on that concern, and questions other recent recommendations for medical intervention which could do more harm than good.

Some backstory on the USPSTF in the likely case that you're not a healthcare nerd: The independent group advises the federal government on the effectiveness of preventive care services and whether their benefits outweigh any possible risks. The USPSTF reviews available evidence on things like screening tests and preventive medicines and then recommends what actions doctors should take, if any, by giving the service a grade from A through D. Healthcare providers aren't required to follow this advice, but it's still consequential: If the USPSTF assigns something a Grade A or B, insurers are required to cover it as a preventive service.

BMJ associate editor Jeanne Lenzer argues that, in the past few years, the USPSTF has been doling out more As and Bs than usual. In the case of depression screening, the recommendations for adults and young people were both Grade B despite a lack of evidence from randomized controlled trials (the gold standard) that screening offered medical benefits. The definition of grade B reads as follows: "There is high certainty that the net benefit is moderate or there is moderate certainty that the net benefit is moderate to substantial."

There are no randomized controlled trials assessing the health outcomes of children screened for depression compared to kids who were not. There has been a randomized trial in adults, though it found that depression screening "leads to a modest increase in recognition rates, but does not have consistently positive effects on patient outcomes." Instead, the task force relied on studies of the accuracy of screening tests and of the benefits and harms of different depression treatments. This is indirect evidence and cannot be considered as providing even moderate certainty.

Another red flag as far as Lenzer is concerned: The reviewers looking at the evidence for children and non-pregnant adults told the BMJ they didn't request unpublished study data from the US Food and Drug Administration, contrary to the agency's own standards. This is problematic because of the phenomenon known as publication bias, the concept that for every study that was published, there could be more research with negative results that never sees the light of day and the absence of this data in a review makes the net benefits appear greater than they really are.

"In the absence of any trial evidence that screening would benefit patients, there is real concern that these recommendations may lead to more harm than good," Brett Thombs, professor of psychiatry at McGill University told the BMJ.

What's the harm in blanket screening for depression, you might ask? A screening questionnaire might pick up on short-term sadness that would eventually resolve on its own, but without ways to detect false positives, some people might spend unnecessary time and money getting an additional assessment from a psychologist. There are others who will be given antidepressants they don't need by their primary care doctor, including SSRIs which the USPSTF acknowledges are associated with increased suicidal behaviors in people ages 18 to 29. And to add insult to injury, some of the common depression screening tests were made by pharmaceutical companies, including the Patient Health Questionnaire (PHQ), which was developed with funding from Pfizer, maker of multiple antidepressants.

As Allen Frances, a psychiatrist and critic of overdiagnosis, told the BMJ, "We don't need to create an army of mislabeled healthy people. We should first take adequate care of people who are already sick and in urgent need."

None of this is to say that doctors shouldn't screen people they suspect might be depressed; it just means that right now, there's no good evidence that doctors should have this conversation with every patient.

Read this next: How to Know If You Need Therapy