A meta-analysis is a very simple thing to do, in some respects: you just collect all the results from all the trials on a given subject, bung them into one big spreadsheet, and do the math on that, instead of relying on your own gestalt intuition about all the results from each of your little trials. It’s particularly useful when there have been lots of trials, each too small to give a conclusive answer, but all looking at the same topic.
