Nudging guideline uptake: A randomized trial of physician public commitments

“Nudges” that influence decision-making through subtle cognitive mechanisms have been shown to be highly effective in a wide range of scenarios, but few experiments applying these interventions to improve clinical practices have been conducted. We conducted a field experiment investigating the effects of a public commitment “nudge” on rates of inappropriate antibiotic prescribing to adults with acute respiratory infections (ARIs). The intervention consisted of displaying poster-sized public commitment letters in exam rooms for 16 weeks. These letters featured clinician photographs and signatures, with clinicians stating their commitment to avoid inappropriate antibiotic prescribing for ARIs.  Nine hundred fifty-four adult patients were treated during the study timeframe: One group (n = 449) was treated by clinicians randomized to the posted commitment letter condition (335 in the baseline period; 114 in the intervention period), and a second group (n = 505) was treated by clinicians that were randomized to a standard practice control condition (384 baseline, 121 intervention). Using electronic health record data, we calculated antibiotic prescribing rates for antibiotic-inappropriate ARI diagnoses pre and post-intervention to estimate the intervention effect.  Baseline rates of inappropriate antibiotic prescribing for ARIs were 41.7% and 45.1% for control condition and poster, respectively.  During the intervention period, inappropriate prescribing rates increased to 48.8% in the control condition but decreased to 36.0% in the posted commitment letter condition.  Controlling for baseline prescribing rates, the posted commitment letter resulted in a 16.2 percentage point decrease in the inappropriate antibiotic prescribing rate relative to control (p=0.017). There was no evidence of a diagnostic coding shift, and rates of appropriate antibiotic prescriptions to patients did not diminish over time.  The effect of this simple, low-cost intervention is comparable in magnitude to costlier and more intensive quality improvement efforts.