Time of Day and the Decision to Prescribe Antibiotics

Clinicians make many patient care decisions each day. The cumulative cognitive demand of these decisions may erode clinicians’ abilities to resist making potentially inappropriate choices. Psychologists, who refer to the erosion of self-control after making repeated decisions as decision fatigue,^1,2 have found evidence that it affects nonmedical professionals. For example, as court sessions wear on, judges are more likely to deny parole, the “easier” or “safer” option.³

In primary care, prescribing unnecessary antibiotics for acute respiratory infections (ARIs) is a common, inappropriate service. Clinicians may prescribe unnecessary antibiotics—again, the easy, safe option—due to perceived or explicit patient demand, a desire to do something meaningful for patients, a desire to conclude visits quickly, or an unrealistic fear of complications.^4,5 We hypothesized that decision fatigue, if present, would increase clinicians’ likelihood of prescribing antibiotics for patients presenting with ARIs as clinic sessions wore on.

The protocol for this study was approved by the Partners HealthCare Human Research Committee, including a waiver of patient informed consent. We merged billing and electronic health record data for patient visits to 1 of 23 Partners HealthCare–affiliated primary care practices between May 1, 2011, and September 30, 2012. We identified visit diagnoses using billing codes, and, using electronic health record data, identified visit times, antibiotic prescriptions, and chronic illnesses.⁶

We analyzed ARI visits by adults (aged 18-64 years), which occurred during two 4-hour sessions—8 am to noon and 1 pm to 5 pm—Monday through Friday. We excluded visits by patients with chronic illnesses (eg, cancer, diabetes mellitus) or concomitant acute diagnoses (eg, skin infections) for which antibiotics would be indicated. We excluded clinicians who had fewer than 40 ARI visits during the study. Consistent with national guidelines, we classified specific ARI diagnoses as antibiotics sometimes indicated or antibiotics never indicated (Table).⁶

Clinicians worked in 4-hour morning and afternoon sessions; many clinicians worked only 1 session on a given day. We used the scheduled hour of each ARI visit (1 through 4) to represent visit time.

Using logistic regression, we estimated the probability of antibiotic prescribing for ARI visits as a function of session hour, number of visits per session, calendar month of visit, patient-level confounders (Table), and fixed effects for clinicians. We used generalized estimating equations to account for clinician-level clustering. We used SAS (version 9.3, SAS Institute) and considered P  < .05 statistically significant.

There were 21 867 ARI visits to 204 clinicians in 23 practices that met our inclusion criteria; 44% resulted in antibiotic prescriptions (Table). Antibiotic prescribing increased throughout the morning and afternoon clinic sessions for antibiotics sometimes indicated and antibiotics never indicated ARIs (Figure). Relative to the first hour of a session, the adjusted odds ratios of antibiotic prescribing in the second, third, and fourth hours were 1.01 (95% CI, 0.91-1.13), 1.14 (95% CI, 1.02-1.27), and 1.26 (95% CI, 1.13-1.41), respectively (P < .001 for linear trend).

We found that primary care clinicians’ likelihood of prescribing antibiotics for ARIs increased during clinic sessions, consistent with the hypothesis that decision fatigue progressively impairs clinicians’ ability to resist ordering inappropriate treatments.

This finding should be interpreted in the context of the study design: we studied ARI visits in a single health care system, scheduled time was a proxy for actual visit time, and unmeasured confounding is possible. In addition, we used visit time as a proxy for decision fatigue, but other accumulating factors (eg, glucose depletion or general fatigue) could contribute to our findings.

Remedies for decision fatigue might include time-dependent decision support, modified schedules, shorter sessions, mandatory breaks, or snacks.³ Further studies could clarify the sources of the problem and test corresponding solutions.

Corresponding Author: Jeffrey A. Linder, MD, MPH, Division of General Medicine and Primary Care, Brigham and Women’s Hospital, 1620 Tremont St, BC-3-2X, Boston, MA 02120 (jlinder@partners.org).

Published Online: October 6, 2014. doi:10.1001/jamainternmed.2014.5225.

Author Contributions: Dr Linder had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Study concept and design: Linder, Doctor, Friedberg, Meeker, Fox.

Acquisition, analysis, or interpretation of data: All authors.

Drafting of the manuscript: Linder, Fox.

Critical revision of the manuscript for important intellectual content: All authors.

Statistical analysis: Linder, Friedberg, Reyes Nieva, Birks.

Obtained funding: Linder, Doctor, Meeker, Fox.

Administrative, technical, or material support: Linder, Doctor, Reyes Nieva.

Study supervision: Linder, Reyes Nieva.

Conflict of Interest Disclosures: None reported.

Funding/Support: This work was supported by grant RC4 AG039115 from the National Institutes of Health/National Institute on Aging.

Role of the Funder/Sponsor: The funding source had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Previous Presentations: This study was presented in part at AcademyHealth; June 24, 2013; Baltimore, Maryland; and at IDWeek; October 4, 2013; San Francisco, California.

Additional Contributions: Dwan Pineros, BA, Geisel School of Medicine at Dartmouth, provided assistance with the data analysis. He did not receive financial compensation.