FRIDAY, Feb. 1 (HealthDay News) -- Medical schools' policies about accepting gifts from drug companies may affect doctors' prescribing habits over the long term, new research suggests.

Because it has become common for medical schools to implement policies that put restrictions on gifts to doctors from drug and medical device makers, the investigators wanted to find out what effect these policies might have on doctors' prescribing behavior once they graduate.

In the study, published online Jan. 31 in the BMJ, researchers found that U.S. doctors who graduated from medical schools that restricted gifts from drug makers are less likely to prescribe new medications over existing alternatives.

The study was based on information from 14 U.S. medical schools where gift restriction policies had been enforced since 2004. The investigators reviewed doctors' prescribing patterns in 2008 and 2009 for three newly introduced drugs to treat mental health problems, according to a journal news release.

"Our findings suggest that conflict of interest policies, which have been increasingly adopted by medical schools since 2002, may have the potential to substantially impact clinical practice and reduce prescribing of newly marketed pharmaceuticals," wrote Marissa King, an assistant professor of organizational behavior at the Yale University School of Management, and colleagues.

"Future research examining the effect of these policies on medications with varying levels of innovativeness is necessary to establish whether medical school gift restriction policies reduce prescribing of all newly marketed medications or affect prescribing selectively," they added.

More information

The American Medical Association provides answers to frequently asked questions about doctors and ethics.