I remember reading a study on sleep quality, purportedly testing whether people sleep better after reading a print book compared to a digital book. If I remember correctly, this is also one of the studies cited for the “blue light bad” trend.
The study found that reading digital books vs print harmed sleep. Their test conditions were something like this (note: I’m not exaggerating how ridiculous the setup was):
Print book: sit/lay in bed however you wish in a moderately lit room and read for some number of hours before you sleep.
Digital book: in the same room with the same lighting, an iPad is attached to a a device that holds it a prescribed distance from your face. The device cannot be moved, so you must sit in a particular position for the entire reading time. THE IPADS BRIGHTNESS SET TO MAXIMUM. You cannot adjust the brightness.
Yeah, I’m probably going to sleep worse after being forced to sit in the same position for multiple hours while being blinded.