A mistake we all make sometimes is attributing an improvement to whatever we've tried recently. For instance, we may get medicine from a doctor (or go to an acupuncturist) and feel better, so we conclude it worked. But did it actually work, or was it just chance? Here's a trick to help you decide: What matters (evidence-wise) is how likely that level of improvement would have been in that time period if the treatment works relative to how likely that improvement would have been if the treatm...