"Either the results are not clear, and they’re not describing the methodology enough to see why the results should be compelling. In both studies, the results were highly compelling, leading Allergan to test the idea itself in a large study at 35 locations in the U.S. The difference between 30 units of Botox and placebo at three weeks was -4.2 (p value 0.005); at six weeks it was -3.7 (p value 0.053), and at nine it was -3.6 (p value 0.049). (Results are said to be statistically significant is the p value is less than 0.05, so this group just missed.) This happens frequently with studies in depression: the patients in the placebo group do better than expected, leading to a neutral result.

Source: Forbes April 05, 2017 20:19 UTC