One other risk of confounding would be the days not being truly independent of each other. If, for example, caffeine consumed on one day were to affect your sleep quality that night and thus your alertness the next day.
Good point, I also realized that the sleep deprivation as a lagging indicator issue makes things more complicated. That is, there’s some anecdotal evidence (and maybe experimental) that sleep deprivation affects performance not the day after poor sleep but the day after that.
One other risk of confounding would be the days not being truly independent of each other. If, for example, caffeine consumed on one day were to affect your sleep quality that night and thus your alertness the next day.
Good point, I also realized that the sleep deprivation as a lagging indicator issue makes things more complicated. That is, there’s some anecdotal evidence (and maybe experimental) that sleep deprivation affects performance not the day after poor sleep but the day after that.