Would you trust a doctor in a T-shirt?

A senior British doctor has complained that junior members of her profession are getting too scruffy. But since doctors are valued for their skill and knowledge does it really matter what they wear?

The father of Western medicine, Hippocrates, had a clear idea of what a doctor should look like - "clean in person, well dressed, and anointed with sweet-smelling unguents". Hippocrates would probably approve of modern hospitals, which offer "unguents" at every turn in the form of hand sanitiser - but he might take issue with the standard of doctors' dress.

Hospital consultant Stephanie Dancer certainly believes it is in decline. Writing in the British Medical Journal last month, she complained that many junior doctors were abandoning formal shirts and jackets for T-shirts.

"I hear that patients complain that they do not know who the doctor is: no tie, no white coat, no jacket, and no presence," she writes. "Doctors are members of a distinguished profession and should dress accordingly."

The stereotypical image of the (male) doctor doing his rounds in a shirt and tie, topped by a starched white coat, possibly trailing a retinue of nurses and students, became obsolete in the UK six years ago when the government issued dress code guidelines prohibiting dangling ties, long sleeves (including the white coat) and wristwatches.

The aim of the new policy was to cut down on cross-contamination within hospitals, reducing the number of germs doctors carried from one ward to another. But oddly, one of the NHS-commissioned review articles that inspired the dress code said "there were no studies that showed an epidemiological link between uniforms worn in practice and cases of health-care associated infections." It did, however, point to a public perception that doctors carried hospital bugs on their clothes.

This 1961 scene from the British comedy Hancock's Half Hour captures how we traditionally expect doctors to look

Since 2007, UK hospital infection rates have indeed gone down, but according to Dancer - a microbiologist - there is no evidence that this is because of the absence of ties and coats, as hospitals introduced a number of hygiene measures at the same time.

Dancer argues that the dress rules may even be counterproductive. "Scruffiness… also intimates a lack of personal hygiene and lower standards of hygienic behaviour," she writes.

And she is not the only one arguing for the return of the white coat.

Many doctors now wear scrubs outside of the operating theatre - the stethoscope and ID badge are the main clues this is a doctor and not a nurse

Like Dancer, Adam Magos, a consultant gynaecologist at the Royal Free Hospital in London says the studies that led to the new policy were flawed and misinterpreted.

"From memory, the one thing that they did find is that the public don't like to see healthcare workers - nurses, doctors - going outside the hospital in their uniform and then coming back in, which I quite agree with," he says. "But that's not the same thing as saying if you're wearing certain apparel - such as white coats in the case of doctors - that patients consider that to be a health risk."

Dr Adam Magos has become adept at tying bow ties

Magos reluctantly hung up his white coat for good in 2009. "I decided to try a bow tie to help with identification. I believe this to have been successful and regularly receive them as gifts from both patients and trainee doctors," he says.

Another doctor, writing in response to Dancer's BMJ article, describes a surgical procedure in which he "amputated" the sleeves from his white coat in order to comply with the regulations. This short-sleeved white coat is occasionally seen in the UK - for example, at Guy's and St Thomas' Hospital - but it's much more common in India.

In the US, the American Medical Association has mulled introducing UK-style dress codes, but for now the white coat remains the most powerful symbol of medicine there.

In a 2005 study published in the Medical Journal of America, 400 patients and visitors to a veterans' outpatients clinic were shown one of four sets of photos of doctors (all four sets were the same, except for the sex and ethnicity of the doctors).

Each set of photos showed:

• a doctor in "business" attire, wearing a smart jacket and tie, with a stethoscope

• the same doctor in "professional" attire of starched white jacket, still with the shirt and tie and stethoscope

• the same doctor in scrubs and trainers with a stethoscope

• the same doctor in T-shirt, jeans and trainers, with stethoscope

The 400 respondents were asked a series of questions, such as: "Which would you prefer to be your family doctor?", "Which of these doctors would you trust the most?" and "Which of these doctors would you expect to be most knowledgeable and competent?"

On average, across all the questions, 76% of respondents chose the professional attire of starched white jacket, followed by scrubs and business dress. The casual look attracted just 4.7% of the vote, although it scored more highly in questions that probed whether doctors looked "caring and compassionate".

This might surprise those who see the white coat as a symbol of old-fashioned, patrician medicine, in conflict with the more modern idea of a partnership between doctor and patient.

The white coat was adopted by 19th Century physicians keen to align themselves with the world of science. As medicine moved from the home to the hospital, the garment became a way of legitimising what would otherwise be taboo behaviour.

"Patients tell doctors very private information that sometimes they don't even tell their spouse," says Dr Mark Hochberg of New York University School of Medicine. "So it's not so much that the doctor is demanding respect but in fact the converse - that a patient wants to feel that he is talking to a person of seriousness, competence and compassion. It's hard to conjure that up if your doctor looks like the guy sitting next to you on the bus."

A patient's trust in his or her doctor is seen as a vital prerequisite for ensuring they follow expert advice. In a 1999 study by David Thom, 62% of patients in the quartile that trusted their doctor most reported that they always took their medication and followed their doctor's advice, compared with 14% of patients in the lowest trust quartile.

But while the white coat remains a powerful symbol in the US - college students even undergo the "white coat ceremony" when they start their studies - a 2002 study of Australian doctors found that a full 98% did not wear white coats.

In the US, doctors will always be found wearing ties in some areas, but in other parts - such as the Pacific Northwest - open shirts are not unknown.

Meanwhile, many European doctors are confused by what they see as the Anglo-Saxon habit of dressing up for a boardroom meeting before doing clinical work.

Dr Jon Laake, an anaesthetist at Oslo University Hospital, says some British doctors dress for hospital as if they were attending a boardroom meeting.

"Most people in Scandinavia would be a bit surprised," he says, "if they saw a visiting surgeon like the ones I saw in two London hospitals, who came in crisp white shirts with cufflinks and pin-striped suits,"

You can listen to Health Check on the BBC World Service. Listen to the episode about overweight doctors via iplayer or browse the Health Check podcast archive.

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