The UK government’s (ever so slightly creepily named) “Behavioural Insights Team” released a report [PDF] (relatively) recently called “Test, Learn, Adapt” (the authors include Ben Goldacre, well known for the book “Bad Science”, and the director of the York Trials Unit, David Torgerson) arguing that more policy decisions should be made on the basis of evidence from randomised controlled trials (RCTs). The report is a really good plain-English explanation of what RCTs are and how they work. It also gives examples of how RCTs can perhaps help to inform policies, by testing whether interventions such as back-to-work schemes or educational programs, um, “work”. According to the report’s blurb:
RCTs are the best way of determining whether a policy or intervention is working.
It’s not hard to find opinion pieces backing up the report’s central idea, and the thesis that RCTs are the best way to “find things out”. Here’s one by Tim Harford, a writer who covers economics; a similar argument made by Paul Johnson who is the director of an economics research group, the Institute for Fiscal Studies; and Prateek Buch, who is a research scientist. A phrase that keeps popping up is “gold standard”. RCTs are “the gold standard in evidence”, says Johnson, or the “gold-standard for showing that medical interventions are effective” according to Buch. Mark Henderson’s book, “The Geek Manifesto” says that the RCT is “commonly considered the ‘gold standard’ for medical research because it seeks systematically to minimise potential bias through a series of simple safeguards”. What exactly does all this mean? I think it’s a question worth asking, since not all science involves RCTs. The Higgs boson for example, was recently “discovered” (if that’s the word) without (as far as I can tell) the need to randomise test subjects. So are RCTs in fact the “gold standard”?

