Jonathan Jarry’s short video on the problems with anaecdotal evidence for “alternative medicine” is a powerful, easy-to-digest primer on the ways that confounding variables, survivor bias and regression to the mean can make stuff like reiki seem like it works, and how double-blind tests can uncover these problems and help us figure out what works and what doesn’t — especially important is the idea that “dead men tell no tales”; that is, no one who died because alternative medicine failed to help them will ever tell you how great it worked. (via Motherboard)