Sponsors get the answer they want.

Before we get going, we need to establish one thing beyond any doubt: Industry-funded trials are more likely than independently funded trials to produce a positive, flattering result. This is our core premise, and one of the most well-documented phenomena in the growing field of “research about research.” It has also become much easier to study in recent years because the rules on declaring industry funding have become a little clearer.

We can begin with some recent work. In 2010, three researchers from Harvard and Toronto found all the trials looking at five major classes of drug — antidepressants, ulcer drugs and so on — and then measured two key features: were they positive, and were they funded by industry? They found over 500 trials in total: 85 percent of the industry-funded studies were positive, but only 50 percent of the government-funded trials were. That’s a very significant difference.