Science isn't a democracy, we need a consensus but we don't need 5000 experts to sit around and say something is the truth to make it so. I agree 8 to 16 is tiny but what if the 8 to 16 are the leading experts in the field? Looking at it in a much wider context, not just this study, from my knowledge of pharmacology, i would say it is reasonably accurate on a relative basis.
Science is not a democracy. Nor is it a consensus. Science is based on falsifiable facts. How do the opinions of a few experts constitute as falsifiable facts?
Let's for now even disregard the above, and just talk about statistics. The vote is on a discrete 0,1,2,3 scale. How could you end up with a score of 2.5, for example? One way is to have a split of 50-50 of people voting for 2 and 3 (any other distribution would give greater variances). The minimum standard deviation is 0.5. Even if we only consider

uncertainties, we still cannot make any meaningful comparisons between a value of

and

.
If you want to justify your claim using evidence from a much wider context, then cite the relevant facts.
Don't purport pseudoscientific reasoning as scientific reasoning.