One-sided significance threshold of less than 0.1 in Phase 2 clinical trial

This sort of trial is pretty common.

Using a generous significance threshold is defensible if the trial’s aim is just to establish if the new treatment could be beneficial (the classical Phase 2 aim). But if that is really the aim then you probably don’t want to recruit to 172 patients (they don’t say how long that took but suspect it was quite a long time). Given the large difference that was found, they could have stopped the trial much earlier with suffcient evidence that the intervention was promising.

So I’m not sure whether the aims changed a bit or were always more than just “phase 2”. It’s good that they randomised though, and that the result was so positive. I do worry a bit about labelling a trial as “phase 2” and thereby justifying a generous threshold for regarding it as “positive,” but then actually running a more defintive trial.

Best solution is surely to get away from p-value thresholds completely…