Last week we discussed systematic reviews, and why they're better than review articles, or opinions. But they're not the only types of "studies of studies" I've presented to you. Sometimes you can go a step further. After you've collected all the appropriate studies, you can merge the data together and do one large analysis. Those studies are called meta-analyses, and they're the subject of today's Healthcare Triage For those of you who want to read more or see references, look here: http://theincidentaleconomist.com/wordpress/?p=57918 John Green -- Executive Producer Stan Muller -- Director, Producer Aaron Carroll -- Writer Mark Olsen -- Graphics http://www.twitter.com/aaronecarroll http://www.twitter.com/crashcoursestan http://www.twitter.com/realjohngreen http://www.twitter.com/olsenvideo