An RCT is a "randomized controlled clinical trial."
We have discussed the scientific fallacy of "data mining" here in the past in which, instead of testing an hypothesis (aka the Scientific Method), the researcher simply asks the computer to find any correlations in the mountain of collected data. That is not science. This is typically done when a researcher has a mound of data which did not support his hypothesis. So as not to waste it, he asks the computer to find something else in it.
In any mountain of data, some correlations can be found if only by laws of randomness - see the legal hoax of so-called Cancer Clusters.
Often enough, when you read "Study says...", you are reading a report from data mining. Our readers know that a statistical correlation often - or usually - means nothing, but data-mining "information" is non-information. Generally speaking, newspaper reporters never passed Statistics 101. (I did, but found stats difficult to explain to innumerate juries who even get confused by basic algebra.)
Junkfood Science discusses Beware the RCT. One quote:
Even medical professionals get taken by this growing technique. It's most common when secondary studies use the database from participants in a randomized controlled trial to look for correlations not to scientifically test a hypothesis, let alone one the original trial had been designed to fairly test. Carefully controlled clinical trials are concerned with causes and effective treatments. In contrast, multivariate analyses of large databases, with their statistical manipulations and regression computer modeling, are statistics. Statistics is about correlations. It's not biological research.
