As you may suspect, it's not that simple.  Our favorite   P-value <0.05 comes straight from statistics, the dreaded MATH class, whereby several different tests can all be used to reject a null hypothesis... when the math states the statistical significance is <0.05 then the null hypothesis is disproven.  In this case, drugs, the medication is likely the cause for the improvement in the patient's condition, and not random chance.  But statitstical significance is used in much more than just science, it's used in many disciplines.

Straight from Wikipedia:  "Statistics rarely give a simple Yes/No type answer to the question under analysis. Interpretation often comes down to the level of statistical significance applied to the numbers and often refers to the probability of a value accurately rejecting the null hypothesis (sometimes referred to as the p-value). " Here's the link to the whole dry article ;)  https://en.wikipedia.org/wiki/Statistics#Data_collection

So, medicine and the FDA are aware, though still our main mathematical marker,  that it's imperfect, and I believe that's why BTD was given!  

I believe this is gonna fly, FWIW, GLTA.... homestretch!