Health: What the Experts Say (cont.)

"If your child has a psychiatric condition for example, you might be penalized for talking about that with your doctor if your employer finds out. That is a high bill that your employer might want to avoid paying.

"If there is something that can be done therapeutically, you need to tell your doctor about your problem. Alcohol or drug use you may be embarrassed about, you may not want to fess up, but you may want to tell the truth about something so important to your health. If you are having an affair and get a venereal disease, yes, it's hard to tell your doctor -- but it is up to you to tell, because there is a treatment and you'll need it. So will your partner.

"If on the other hand you have a pre-existing condition and there is nothing medicine can do -- say you've got the Huntington's gene, or the gene for early-onset breast cancer -- if there is no good my doctor can do me and only harm can befall me, why tell? This is not lying but withholding the truth."

Roberts: "Are there good reasons to lie to doctor? No. Reasonable reasons? Not really. It is silly to pay a doctor for an opinion and have him base that opinion on less than 100% of the truth."

Klitzman: "Yes, particularly with genetic tests that show a high risk of disease. The doctor may not say, 'Whatever you tell me won't go in the record.' But around genetic diseases, or with self-insured businesses, people may not want their employer to know things. This is something you can say to your doctor.

"Now if it is something like, 'I am beating my son' -- that the doctor must report. But if it is a legitimate concern, the doctor may say that if it is not medically relevant, it needn't go into the record. A lot of doctors don't think and put everything in the chart. Yet maybe a lot of things don't belong in a chart."

WebMD: Why do people lie to their doctors?

Klitzman: "It is specifically about taboo areas. One is adherence to treatment. Lots of patients don't do what the doctor says, but are afraid the doctor will get mad if they say so.

"Another is substance abuse. We were taught to double what the patient says. So if a patient says, 'I drink only two glasses of wine a night,' the professors would say that means four. If they say they take cocaine twice a week, that means four times a week.

"And another taboo is the area of sexual behavior, everything from homosexuality to extramarital relationships. The doctor will say, 'Are you practicing safer sex?' and they will say yes when they are not. They aren't saying, 'I usually do, but there was this time we had a few beers and we forgot the condom,' or, 'We got carried away the other night.' It's just a taboo area."

Caplan: "If people are honest about their conditions they may fear risking loss of job or insurance. They also may lie to ensure access to medical services. And they may lie so that they can get insurance reimbursement for a condition. They also lie out of humiliation or to protect a spouse.