Doctors with a profile on the social networking site Facebook may be compromising the doctor-patient relationship, because they don't deploy sufficient privacy settings, indicates research published online in the Journal of Medical Ethics.

The authors base their findings on a survey of the Facebook activities of 405 postgraduate trainee doctors (residents and fellows) at Rouen University Hospital in France. Half those sent the questionnaire returned it.

Almost three out of four respondents (73%) said they had a Facebook profile, with eight out of 10 saying they had had a presence on the site for at least a year. Those with a profile tended to be slightly younger than those who didn't.

One in four (24%) logged on to the site several times a day, but almost half (49%) logged on once a day or several times a week. The rest were rather more infrequent users of the site.

Almost half believed that the doctor-patient relationship would be changed if patients discovered their doctor held a Facebook account. But three out of four said this would only happen if the patient was able to access their profile.

Virtually all (97%-99%) displayed sufficient personal information for them to be identified, including their real name and their birth dates. And 91% displayed a personal photo. Just over half displayed their current post (55%) while 59% provided information on their current university training site.

Over half claimed to change at least one of the default privacy settings (61%), but 17% couldn't remember if they had done this. Those who had been on the site for under a year were less likely to limit access to the content of their profile.

Only a few Facebookers had received a friend request from a patient (6%), four of whom accepted it. But such requests are likely to become more common, suggest the authors

While most respondents (85%) said they would automatically refuse a friend request from a patient, one in seven (15%) said they would decide on a case by case basis.

The reasons given for accepting a patient as a friend included feeling an affinity with them and fear of embarrassing or losing that patient if they declined.

The need to keep a professional distance or the suspicion that the patient was interested in a romantic relationship, were the primary reasons given for rejecting the request. Although a high proportion of doctors considered that such interaction might be unethical, this reason came bottom of the list.

"This new interaction (whether it is romantic or not) results in an ethically problematic situation because it is unrelated to direct patient care," say the authors.

"Moreover public availability of information on a doctor's private life may threaten the mutual confidence between doctor and patient if the patient accesses information not intended for them."

And they warn: "Doctors must be aware that comments and pictures posted online may be misinterpreted outside their original context and may not accurately reflect their opinions and real-life behaviour. This information could also become accessible to people that it was not intended for."