A couple of weeks ago, internist Ashish Jha was working at Boston's Brigham and Women's Hospital on a Friday afternoon. A patient showed up with a really complicated abscess in his abdomen. "I remember saying to my team, ‘It’s unfortunate the patient came in on a Friday afternoon. It would have been easier if this was a Thursday,'" he said.

Jha wanted to find another physician who had a good technique for draining the pocket of fluid that was causing pain in the patient's belly, but he knew it’d be hard to get that exact person to come in late on a Friday.

The anecdote highlighted an uncomfortable truth about hospitals. A patient’s fate can sometimes be determined, at least in part, by the day and hour of the week he comes in.

In this particular case, Jha said, it didn't matter much: The patient got perfectly fine care. Still, getting that person matched with the right doctor and treated in time was a lot more challenging on a Friday afternoon than it would have been on, say, a Monday morning. And there are times when this mismatch can potentially make an even bigger difference — like weekends and holidays.

"All else held equal, it’s better to avoid the hospital on weekends or holidays," said Jha, an expert on health care quality.

Hospitals have worse outcomes on weekends and holidays — but it's not clear why

The effect that weekends and holidays can have on patient care remains contentious, despite extensive research on the subject.

Some studies have found that patients with a variety of health conditions tend to face a slightly greater risk of death if they're admitted to a hospital during the weekend instead of during the week. But the evidence here remains mixed, and the effect sizes in studies can vary a lot depending on the number of patients involved.

Even if hospitals do have worse outcomes on weekends and holidays, it's not entirely clear why that might be. There may be a selection effect at work. For example, it might be that people engage in riskier behaviors during their free time that is more likely land them in the hospital. (Alcohol comes to mind.) Or perhaps some patients with illnesses during the week wait until the weekend before going to the hospital — at which point their condition is worse than they would've been if they'd gone in right away.

But there's also some reason to think that hospital care is different during holidays and weekends, and perhaps slightly lower quality. The health professionals who get stuck working these hours tend have less seniority and experience. And the staffing might be thinner. That might explain the poorer health outcomes, at least in part.

For what it's worth, many of the doctors I spoke to about this topic were not convinced that the "weekend effect" is all that significant. As Jha said, "We shouldn't be overly dramatic — the evidence is not overwhelming or crystal clear." Nor were they persuaded that the quality of care patients get is necessarily lower.

That said, they did concede that the staff coverage tends to be lighter, which can cause delays and hassles for patients and doctors. And they had some advice for anyone who ends up in the hospital during one of these days.

Be patient — you'll probably face longer wait times

If you’ve ever been to a hospital on a weekend or holiday and ended up waiting for hours to be discharged, there’s a pretty simple explanation for that: There are fewer health professionals, lab technicians, and diagnosticians around.

The thinner staffing doesn't generally affect urgent care. "If there’s an emergency or something that needs to be addressed right away," said Jason Block, a physician and researcher at Harvard Medical School, "it can be addressed over the weekend or holiday just like any other time."

"But what does change," he added, "is the ability to do diagnostic testing [like a CT scan or MRI] or the ability to get people released from hospital in a prompt time." Even if that's not dangerous for the patient, it can be a bit annoying.

Staffing shortages can be especially bad around Thanksgiving and the Christmas holidays, which align with flu season when some staff may be off sick, said University of Toronto internist Paul Bunce. "We’ve had flu outbreaks on the holiday block, which really strained our staffing," he recalls. "Staffing is a bit less robust, and unexpected absences from things like infectious outbreaks can be even more challenging to manage."

That means that those with less urgent problems end up waiting a lot longer. It also makes doctors' jobs more difficult. "Patients accrue, the workload increases, and it becomes harder to manage patients," said Bunce.

Patients should be ready to speak up

Harvard’s Jha said he’s always able to get patients the care they need during off-hours. But it can take an enormous amount of effort to coordinate with other medical staff. "I need to push people," he said. "I get a lot of grumpy voices on the phone."

During weekends and holidays, doctors and nurses may be a little more rushed when they’re caring for patients. They may not have the bedside manner they usually do. It also means you may need to advocate for yourself a little more and speak up if you’re not getting the care you need.

"Hospitals are very complex environments with lots of moving parts," said Block. "There are lots of people involved in care. And it’s easy for things not to happen unless there’s some type of advocate for patients." That's as true on an off-day as it is any other time of the year.