As doctors got more fatigued, they defaulted to the easy thing: just writing an antibiotic prescription rather than taking the time to explain to patients why it is not necessary. As the day went on, doctors’ fears of disappointed, dissatisfied, angry or confrontational patients may have loomed larger and larger. The will to confront those fears may have dwindled and more patients left the clinic with unnecessary antibiotics.

This same pattern of doctors defaulting to the easy thing later in the day has appeared for decreased influenza vaccinations, increased opioid prescribing for back pain and decreased physician hand-washing. We doctors like to think of ourselves — and the public might like to think of us — as rational decision makers, but depending on the time of day, treatments change.

What can be done? Half the battle is knowing this exists, finding a plan to compensate and maybe taking a quick break. But scheduling mandatory breaks doesn’t cut down the amount of work. Certainly, improving the efficiency of the current generation of electronic health records would help things go more smoothly in the office.

Most cancer screening and preventive services could be done outside of face-to-face visits by support staff. This would allow doctors to focus on necessary care in the moment. But that requires big changes to most health insurance, which still largely pays only for in-person visits.

Doctors might not be the only ones who are impaired later in the day. In the new study, patients with late-afternoon appointments had lower screening rates even one year later. Late-day fatigue may have made patients less likely to make necessary after-visit cancer screening arrangements.

If doctors were paid based on the quality of care we delivered instead of face-to-face visits, clinics and health systems might make sure that doctors and patients at the end of the day have more effective reminders about follow-ups, more support staff or even longer visits.

So what can you do when you find yourself with a 4 p.m. checkup? After all, not everyone can get the early-morning appointment. Prepare. Learn about screenings you might be eligible for, work with your doctor to figure out which are right for you. Once screening or follow-up tests are ordered, make the necessary follow-up arrangements right away.

And consider having that cup of coffee before your visit.

Jeffrey A. Linder is a professor and chief of the division of general internal medicine and geriatrics at the Feinberg School of Medicine at Northwestern.

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