In double-blind experiments, at least some participants and some experimenters do not possess full information while the experiment is being carried out. Double-blind experiments are most often used in clinical trials of medical treatments, to verify that the supposed effects of the treatment are produced only by the treatment itself. Trials are typically randomized and double-blinded, with two (statistically) identical groups of patients being compared. The treatment group receives the treatment, and the control group receives a placebo . The placebo is the "first" blind, and controls for the patient expectations that come with taking a pill, which can have an effect on patient outcomes. The "second" blind, of the experimenters, controls for the effects on patient expectations due to unintentional differences in the experimenters' behavior. Since the experimenters do not know which patients are in which group, they cannot unconsciously influence the patients. After the experiment is over, they then "unblind" themselves and analyse the results.
The most-tweeted about article, a psychology study investigating whether or not sexist video games imparted sexist attitudes or mindsets onto the people who played them, was also an outlier. The study shared the most via Facebook, on the other hand, was about Homo erectus using shells as tools. Neither, clearly, involved health or environment. “We’re definitely seeing social media amplify studies that the mainstream media wouldn’t pick up,” Konkiel says. “As long as there’s an active community on social media, we see stories that otherwise might be niche get a lot of attention as measured by our score.”