Four out of five doctors in a national survey said they let drug and device makers buy them food and drinks despite recent efforts to tighten ethics rules and avoid conflicts of interest.

Family doctors were more likely to meet with industry sales representatives, the survey found, and cardiologists were more likely than other specialists to pocket fees.

The study is the first to document the extent of the relationships between doctors and sales reps since 2002, when a leading industry group adopted voluntary guidelines discouraging companies from giving doctors gifts or tickets. In general, researchers found hardly anything had changed.

Consumer advocates say this is proof the new rules aren't working.

"These findings are fairly disturbing. There appears to be no dialing back at all on these relationships," said Merrill Goozner of the Center for Science in the Public Interest.

The survey, published in today's New England Journal of Medicine, was done by researchers from Massachusetts General Hospital, Yale University and the University of Melbourne in Australia.

Questionnaires were mailed in 2003 and 2004 to 3,167 doctors around the nation; 1,662 replied. They included anesthesiologists, cardiologists, family doctors, surgeons, internists and pediatricians with experience ranging from less than 10 years to more than 30 years. Half were in private group practices and the rest worked in hospitals and medical schools.

Responses were anonymous. About 95 percent said they had contact with drug or device companies.

Other findings:

83 percent received food and drinks.

78 percent accepted free drug samples.

35 percent were reimbursed for costs associated with professional meetings.

28 percent pocketed consulting or lecture fees.

7 percent took free tickets to games and other events.

The extent of the interactions varied by specialty. Sales reps tend to target doctors with the most influence. Cardiologists, for example, were more than twice as likely as family doctors to receive fees.

Doctors in private practice were six times more likely to get free samples and three times more likely to get gifts than those at hospitals. Family physicians met with reps far more often than their counterparts - about 16 times a month.

Doctors need to "supervise themselves and set stricter standards on what is appropriate and acceptable behavior," said one of the authors, David Blumenthal, head of the Institute for Health Policy at Massachusetts General Hospital.

The study was funded by the New York-based Institute on Medicine as a Profession. None of the authors reported conflicts of interest for the study.

Previous research has suggested that cozy relationships with industry can affect doctors' prescribing patterns and judgment. But companies have defended the practice as a legitimate way to educate physicians about the latest drugs and technology.

The Pharmaceutical Research and Manufacturers of America, the leading trade group, in 2002 adopted voluntary rules limiting the value of gifts to $100 or less and banning free tickets for entertainment.

Scott Lassman, a senior assistant general counsel with the trade group, said the study's results were "common knowledge" and dismissed claims that companies were out to influence doctors.

"A modest meal is not going to affect the independence of the health-care practitioner," Lassman said.