Countering caregiver placebo effect in pets

[ArkRescue]

"How do you know that your pet is benefiting from its pain medication? A new clinical trial design could help overcome pet owners' unconscious observation bias and determine whether the drugs they test are effective."

http://www.sciencedaily.com/releases/2014/03/140312150231.htm

 

[rabbithead]

And the pain medication was-------------?