Most respondents said they wanted to avoid being judged, and didn't want to be lectured about how bad certain behaviours were.
More than half were simply too embarrassed to tell the truth.
Photograph: Biswarup Ganguly/Wikimedia Commons
We are all guilty of lying to our doctors.
When the doctor asks us things like, how often we exercise or what have we been eating lately, we tend to lie or stretch the truth. It's mostly because we want to avoid being judged.
According to a recent study, 60 to 80 percent of people surveyed have not been forthcoming with their doctors about information that could be relevant to their health.
Besides fibbing about diet and exercise, more than a third of respondents didn't speak up when they disagreed with their doctor's recommendation.
Another common scenario was failing to admit they didn't understand their clinician's instructions.
When respondents explained why they weren't transparent, most said that they wanted to avoid being judged, and didn't want to be lectured about how bad certain behaviors were.
More than half were simply too embarrassed, to tell the truth.
"Most people want their doctor to think highly of them. They're worried about being pigeonholed as someone who doesn't make good decisions," said Angela Fagerlin, senior author on the study.
The results of the research were published in the journal of JAMA Network.
Scientists at the University of Utah Health and Middlesex Community College led the research study in collaboration with colleagues at the University of Michigan and the University of Iowa.
Insights into the doctor-patient relationship came from a national online survey of two populations.
One survey captured responses from 2,011 participants who averaged 36 years old. The second was administered to 2,499 participants who were 61 on average.
Survey-takers were presented with seven common scenarios where a patient might feel inclined to conceal health behaviors from their clinician and asked to select all that they had ever happened to them.
Participants were then asked to recall why they made that choice.
The survey was developed with input from physicians, psychologists, researchers and patients, and refined through pilot testing with the general public.
In both surveys, people who identified themselves as female were younger, and self-reported as being in poor health were more likely to report having failed to disclose medically relevant information to their clinician.
"I'm surprised that such a substantial number of people chose to withhold relatively benign information, and that they would admit to it," said Andrea Gurmankin Levy, first author of the study.
The trouble with a patient's dishonesty is that doctors can't offer an accurate medical advice when they don't have all the facts.
"If patients are withholding information about what they're eating, or whether they are taking their medication, it can have significant implications for their health. Especially if they have a chronic illness," says Levy.
The study suggests that understanding the issue more in-depth could point toward ways to fix the problem. Person-to-person interviews could help identify other factors that influence clinician-patient interactions.
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