RE:RE:RE:RE:RE:Thank you to the objective people.Double-blinded is important because it can differentiate true medicine efficacy from placebo (psychological relief). Some times, physicians give patients placebo for cetain symptoms and so often it works!
The trial was small but its p-value delivers so important information. In order to calculate P-value, or paired student t-test, we need two key measures, between variance and within variance. Between variance is average pain relief, that's 7 points. This number is the larger the better. Within variance is to measure consistency of the paired group pain level improvements. This number is the smaller the better. FDA requires P-value be smaller than 0.05 (i.e.,95% confident level) and ATE-346 P-value is less than 0.001. What it means? It means 7 points pain relief is not something placebo can do. And, the pain relief is so consistent across the 12 people. And therefore, though the sample size is small, it is a robust result.
The other purpose of PII is to identify best dose for PIII, and this is so obvious. If 100mg works, you won't take 250mg. But, we don't know it before this repeating trial.
qwerty22 wrote: There's no logical connection in your argument. Double-blinded is intended to mitigate observer bias, a stats test result does not prove observer bias did not give rise to result any more than it can prove the result came from the action of the drug, it just protects against the result arising from random chance once everything else has been well-controlled against. Not everything has been well controlled in this small trial.
But I'm not arguing the trial wont be a success, there are a number of lines of reasoning to lead you to think this drug is an active NSAID beyond the stats in that small trial. This larger trial meets the requirement from pharma execs to see efficacy in "hundreds" of patients (in a well controlled double-blinded trial). Its also going to give us the added info you talk about.
Actuarial wrote: Two reasons for repeating the test: 1. it was not a "double blind" test; 2. it was "same" dose test. PII is to confirm two things, one is efficacy (vs. placebo), the other is to determin best dose for PIII.
To be honest, for item1, I don't worry too much about it cause its P-value is < 0.001, which is far more than satisfy (0.05 FDA standard). While the sample size is small at 12, it also requires much more stable and consitent results to reach a p-value < 0.001. Paired student t-test indirectly adjust calculation for P-value with respect to sample size.
qwerty22 wrote: Of coutse 12 is too small thats why they are essentially repeating that experiment again now with larger numbers. Its not just statistical tests they need to satisfy.
Actuarial wrote: If you do look for facts, the fact is that 12 people show average pain relief score 7 with P-value < 0.01. I see why you would challenge 12 being too small because obviously you don't understand how P-value was calculated. Google "paired student t-test" and you will understand it is a fair test for both small sample or large sample.