Crossover study designs reduce statistical variance and can yield significant p-values with small sample sizes and short durations by having participants serve as their own controls.

“I guess like the Assumption when I was thinking about it when you're talking about it and you know they serve as their own controls it's almost as if they're treating them like if you could get identical twins and randomize those identical twins to one group or the other you would think that's great because you're controlling for so many things”