It has been said before, but is important to remember that the original word "Establish" is not generally used in FDA documents or guidance to describe acceptable efficacy. The wording that was added "Substantial Evidence" is wording that is commonmly used in FDA guidance to describe efficacy. The wording change was proper and most likely the original question was improperly worded.
The first voting question on safety used the word establish, HOWEVER, later in the question it included the word "Reasonably" safe...If the word "reasonable" was ommitted from that question the same voting problem would have occured for that question.
If the word "reasonable" was included with the efficacy question then it would have read ...Establish Reasonable efficacy...then there would have not been any voting confusion.
IMO, establish means absolute and within the context of talking about drug safety and efficacy nothing is established, especially about drugs that have never been on the market.
IMO, the wording change was necessary and proper.