Many people do their best work in the morning, and new research suggests the same may hold true for doctors.
The study, of nearly 53,000 primary care patients, found that doctors were more likely to order cancer screenings for patients seen early in the day, versus late afternoon.
During 8 a.m. appointments, doctors ordered breast cancer screenings for 64% of women who were eligible for them. That figure declined over the next few hours, rebounded around lunchtime, then fell again as the afternoon wore on: During 5 p.m. appointments, doctors ordered screening for just under 48% of eligible patients.
A similar pattern was seen with colon cancer screening. About 36% of patients with 8 a.m. appointments received a screening order, versus only 23% of those with 5 p.m. appointments.
What's going on? Senior researcher Dr. Mitesh Patel speculated on one explanation: As the day goes on, doctors often fall behind schedule, and may run out of time for cancer screening discussions.
There's "a lot to get done" during a standard appointment, Patel noted -- from routine health checks, to flu shots, to whatever concerns the patient is bringing up.
"So the doctor might think, 'I have limited time. I'll talk about this [screening test] the next time,'" said Patel, an assistant professor of medicine at the University of Pennsylvania.
It's also possible "decision fatigue" is a factor, he said.
If a doctor has spent much of the day talking to patients about cancer screening -- and often hearing "no" -- he or she might let it slide by day's end.
"This is a reminder that doctors are human, too," said Dr. Jeffrey Linder, a professor of medicine at Northwestern University Feinberg School of Medicine in Chicago. "They're laboring under the same psychological and fatigue constraints as everyone else."
Linder wrote an editorial accompanying the study, published May 10 in the journal JAMA Network Open.
"Not everyone can get an 8 a.m. appointment," Linder pointed out. But, he said, it's good for doctors and patients to be aware that time of day might affect their care.
The study is not the first to suggest doctors practice differently as the day wears on.
In an earlier study, Patel's team found the pattern held true with flu shots: Patients seen late in the day were less likely to get them.
Other researchers have found that toward the end of the day, primary care doctors are more likely to inappropriately prescribe antibiotics or opioid painkillers.
It's possible, Patel said, that patients are also in a rush toward day's end, or dealing with their own decision fatigue.
"At the end of a workday," he said, "you might not want to have a conversation about cancer screening."
The findings are based on records from patients in the University of Pennsylvania health system who had primary care appointments between 2014 and 2016. Over 19,000 were eligible for breast cancer screening, while over 33,000 were eligible for colon cancer screening.
Patel and his team looked at whether patients received a screening order at their first appointment during the study period -- and whether they actually went for screening over the next year.
They found that patients with late-day appointments were substantially less likely to be screened: One-third of women with an 8 a.m. appointment underwent breast cancer screening in the next year, versus 18% of those with 5 p.m. appointments. The figures for colon cancer screening were 28% and 18%, respectively.
What to do? Patel said there's a "great opportunity" for technology to help. Patients' electronic health records could be cued to remind doctors to order cancer screenings, for example.
Linder agreed. He also pointed to the low screening rates among these study patients overall. That, he said, suggests that patients need similar nudges, to encourage them to follow up on screening orders.