(CBS NEWS) -- About half of U.S. doctors received payments from the pharmaceutical and medical device industries in 2015, amounting to $2.4 billion, a new study reports.
Those payments and gifts very likely encourage doctors to prescribe pricey brand-name drugs and devices pushed by sales representatives, a second study argues.
Doctors at academic medical centers were more likely to prescribe cheaper generic drugs than expensive brand-name drugs after their hospitals adopted rules that restricted pharmaceutical sales visits, the researchers said.
Restrictions on sales visits were associated with a reduction in prescriptions for brand-name drugs, said lead researcher Ian Larkin, an assistant professor at the University of California, Los Angeles Anderson School of Management.
"If a doctor was prescribing that drug 100 times a month, our estimate is it would go down to about 92 times a month after the restrictions were put in place," Larkin said. "That's actually a very substantial change."
Drug companies earned more than $60 billion in 2010 for brand-name drugs included in the study, Larkin and his colleagues noted. Generic drugs are 80 to 85 percent less expensive, which means hospitals can save lots of money if doctors start prescribing generics instead of brand-name drugs.
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