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

The long awaited drug test on Floyd Landis' backup urine sample begins today in a French lab.

NPR: Landis Facing Uphill Battle on Doping Charges

Peter Cohen, of the Centre for Drug Research at the University of Amsterdam, followed a sample of cocaine users whom he describes as typical.

ECONOMIST: The harm done

The panel also noted that the "evidence suggesting very clearly that the analyitcal results reported by DCC (Drug Control Centre, Kings College London) in connection with the A sample were difficult to interpret".

BBC: Turnbull didn't learn of the positive test for nine months

Other factors that contribute to false results are small sample sizes, studies that show weak effects (such as a drug which works only on a small number of patients) and poorly designed studies that allow the researchers to fish among their data until they find some kind of effect, regardless of what they started out trying to prove.

ECONOMIST: Just how reliable are scientific papers?