Though few comprehensive studies have been conducted, one by the University of Washington investigated how drug sample availability affected what physicians prescribe.

尽管人们几乎没有进行过全面的研究，但是华盛顿大学的一项研究调查了药品样本的可获得性对医生开的处方的影响。

youdao

The court ruled that because federal law prohibits direct sales of prescription pharmaceuticals, no rep actually sells a drug or sample.

FORBES: Magazine Article

Even if physicians consulted with their patients before enrolling them in free sample drug programs, the fact that such programs exist at all is evidence of market forces encouraging the use of prescription drugs.

CNN: Medicine in your junk mail

During the hearing, Braun's side challenged the chain of custody from the time the urine sample was collected by Comprehensive Drug Testing Inc. to when it was sent, nearly 48 hours later, to a World Anti-Doping Agency-certified laboratory in Montreal, two people familiar with the case said.

WSJ: MLB: Ryan Braun's 50-Game Suspension Overturned - Milwaukee Brewers