In management lore, there are all sorts of signs that one of your employees is about to quit.

Some claim you should worry if an employee suddenly starts showing up to work in a suit, or alternatively if someone starts dressing much more casually. Others say it's a red flag if a team member misses work more than usual. In the predigital era, some bosses lurked by the printer to see if employees had left their résumés lying around.

But is any of this folk wisdom actually backed by science? To find out, a pair of management professors recently conducted a series of studies, gathering supposed tells that an employee has one foot out the door and carefully checking them against actual behavior in the real world.

And it turns out that much of what you've heard is, essentially, hogwash. (Get all the details of the research methodology in their write-up for the HBR blogs.)

13 signs that are really one big sign

So what signs that an employee is about to quit actually held up to scientific scrutiny? According to the researchers, these are the 13 true tells:

  1. Their work productivity has decreased more than usual.
  2. They have acted less like a team player than usual.
  3. They have been doing the minimum amount of work more frequently than usual.
  4. They have been less interested in pleasing their manager than usual.
  5. They have been less willing to commit to long-term timelines than usual.
  6. They have exhibited a negative change in attitude.
  7. They have exhibited less effort and work motivation than usual.
  8. They have exhibited less focus on job-related matters than usual.
  9. They have expressed dissatisfaction with their job more frequently than usual.
  10. They have expressed dissatisfaction with their supervisor more frequently than usual.
  11. They have left early from work more frequently than usual.
  12. They have lost enthusiasm for the mission of the organization.
  13. They have shown less interest in working with customers than usual.

But take a closer look at that list and you can quickly see that all of these various behaviors could be described by one simple, everyday phrase: You're in trouble if your employee starts phoning it in.

Each of these behaviors, from lower productivity to more complaining to less interest in pleasing supervisors, is basically an indication that an employee is starting to mentally disengage with the job and is becoming less invested in his or her performance, colleagues, and customers. See your star performer's behavior trending that way and, science can now confirm, you really do have cause for concern.

How to stop someone from quitting

We all know the costs of losing a valued team member are high, so if you notice that one of your best people seems mentally elsewhere, is there anything you can do to change his or her mind? The researchers behind this new study offer a few suggestions.

First, offer the person a sweetener of some sort. "There are many ways to invest in employees you fear may be looking: pay increases, promotions, special projects, etc.," write the researchers. Second, they suggest a technique known as a "stay interview."

"Instead of conducting only exit interviews to learn what caused good employees to quit, hold regular one-on-one interviews with high-performing employees to learn what keeps them working in your organization and what could be changed to keep them from straying," they recommend.

Does your experience match these research findings?