DOCTOR AFTER NOON - 1

IT'S 3 p.m. I've been seeing patients for a few hours and I feel my focus fading. I need to stay sharp for those still to come, so I grab a snack and some coffee.

This has become my afternoon ritual during my 20 years as a primary care doctor. Now, a new study confirms that my feared ''3 o'clock fade'' is real - and that it could affect patients' health.

According to the study, published in JAMA Network Open, doctors ordered fewer breast and colon cancer screenings for patients later in the day, compared to the first thing in the morning.

All the patients were due for screening, but ordering rates were highest for patients with appointments around 8 a.m.

By the end of the afternoon, the rates were 10 percent to 15 percent lower. The probable reasons?  Running late and decision fatigue.

In primary care, doctor's run late because the workload is impossible. To do everything we're supposed to for a typical daily patient load, primary care doctors should spend 11 to 18 hours a day providing preventive and chronic care, never mind addressing new problems.

We spend one to two hours updating the electronic health record for every hour we spend with  patients. To try to fit in what we can, we end up feeling like Lewis Carrol's White Rabbit, constantly behind, checking our watches, harried, rushing from patient to patient.

Decision fatigue - another explanation for the study's findings - is the progressive erosion of our  self-control as we make more and more choices.

Decision fatigue was most famously described in a study of Israeli Judges making parole decisions.

The probability of a prisoner getting parole was highest first thing in the morning or right after a break. The chance of parole dropped as court sessions went on. The chance of getting parole right before a break or lunch?  Basically zero.

Decision fatigue is why car dealership offers you expensive, unnecessary  options at the end of a series of choices and why the supermarket has all that candy right at the  check-out counter.

Your doctor is not immune.

in a 2014 study, my fellow researchers and I found  doctors prescribed fewer unnecessary antibiotic prescriptions for respiratory infections first thing in the morning, but that unnecessary prescriptions gradually increased over the day.

We found the exact same doctor, caring for the exact same patient, had a 38 percent higher chance of writing an antibiotic prescription at 4 p/m. compared to 8 a.m.

The honor and serving of the latest operational research on Doctors and Workings, continues.

The World Students Society thanks author and researcher Dr. Jeffrey A. Linder, chief of the division of general internal medicine and geriatrics at the Feinberg School of Medicine of Northwestern.