The real question, of course, is: why? Why has the placebo effect gotten stronger, and why only in the United States? The study authors have a few ideas. Drug companies in the U.S. market directly to consumers, a practice illegal in much of the rest of the world, which might raise patient's expectations for how well a drug should work. But a more likely reason, the study authors suspect, is that the glossy setting of an expensive, large-scale clinical trial—with professional nurses taking patients' vitals and administering drugs—may raise patients' expectations and convince them of the pill's efficacy, even if it doesn't have any active ingredient. Historically, trials in Europe weren't as large and didn't last as long, which may have offset the effects of the placebo. But it still doesn't fully explain the difference in outcomes across the Atlantic, especially because the two systems are now more alike than ever before.