Physicians may want to dig a little deeper into their closets, or grab their white coats on the way out of the operating room, if they want patients to view them favorably, according to the largest-ever study of patient preferences for doctors’ attire.

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In fact, what medical doctors wear may matter more than most doctors — or even patients — might think, say the researchers behind the new paper in BMJ Open.

Based on the work, researchers call for more hospitals, health systems and practice groups to look at their dress standards for physicians or to create them if needed.

Just over half of the 4,062 patients surveyed in the clinics and hospitals of 10 major medical centers said that what physicians wear is important to them — and more than one-third said it influences their satisfaction with their care. Patient preferences matter in part because hospitals are paid by the Centers for Medicare and Medicaid based in part on scores on patient satisfaction surveys.

“Professional dress on Wall Street, law and nearly every other industry is relatively clear — and it typically mirrors what applicants would wear to their job interview,” says Christopher Petrilli, M.D., lead author of the study and an assistant professor of hospital medicine at the University of Michigan Medical School, who worked in finance before entering medicine.

“In medicine, the dress code is quite heterogeneous, but as physicians we should make sure that our attire reflects a certain level of professionalism that is also mindful of patients’ preferences.”

Patients’ views on physician attire

The study also asked patients to look at pictures of male and female physicians in seven different forms of attire, and to imagine them in both inpatient and outpatient clinical settings. For each photo, they rated the providers on how knowledgeable, trustworthy, caring and approachable the physician appeared, and how comfortable the attire made the patient feel.

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The options were:

Casual: Short-sleeved collared shirt and jeans with tennis shoes, with or without white coat

Scrubs: Blue short-sleeved scrub top and pants, with or without white coat

Formal: Light blue long-sleeved dress shirt and navy-blue suit pants, with or without white coat, with black leather shoes with one-inch heels for women and black leather shoes for men, and a dark blue tie for men

Business suit: Navy-blue jacket and pants with the same dress shirt, tie and shoes as in the “formal” option, without white coat

Formal attire with a white coat got the highest score on the composite of five measures and was especially popular with people over age 65. It was followed by scrubs with a white coat, and formal attire without a white coat.