Why real life needs real trials
Finding out what works is a serious business and this is a brilliantly simple way to do less harm and save money
I sometimes feel that if only politicians and civil servants had a “Ladybird Book of Randomised Policy Trials”, they’d understand why such trials were a brilliantly simple way for Whitehall to do more good, less harm and save money.
Well, I have hugely encouraging news to report: the “Ladybird Book of Randomised Policy Trials” now exists. Better than that, it’s not just some academic flight of fancy. It is the result of a collaboration between two academic experts, Professor David Torgerson and Dr Ben Goldacre, and two civil servants, Laura Haynes and Owain Service, of the Cabinet Office’s Behavioural Insights Team. In other words, something might actually happen.
My enthusiasm is scarcely dented by the fact that the document is actually called “Test, Learn, Adapt: Developing Public Policy with Randomised Controlled Trials”; no Ladybird, alas, although Goldacre tells me he wishes that had been the title.
Randomised trials are important in policy work for exactly the same reason that they are important in medicine: because our theories about what works are often badly wrong, and in a complex world it is often only a properly controlled trial that will set us straight.
A good example in medicine is the use of steroid injections for people with head injuries, to reduce swelling and brain damage. The theory was sound – so sound that many doctors argued that it was unethical to conduct a randomised trial. Yet when the trial was eventually run and published, in 2005, it turned out that the well-meaning steroid injections had been inadvertently killing people.
There are similar examples among the few randomised trials of policy. “Scared straight” programmes, designed to warn juvenile delinquents of the consequences of a life of crime, turn out to cause crime, alas.
You might think it is far harder to run a trial on a social programme than in medicine, but Torgerson, director of the York Trials Unit, tells me the opposite is true. Clinical trials are difficult – patients often wander off or drop out. By contrast, many of the trials one might do in a school or prison involve people who were going to be there anyway.
The difference is in our priorities. Torgerson points out that he recently spent £500,000 testing verruca treatments; for the same money he could find out whether phonics is an effective method for teaching children to read.
So why is it so hard to get funding, and approval, for randomised policy trials? One common objection is that we don’t need trials because we already know what works. This is nonsense, of course: very often different experts or political parties “know” things that are mutually contradictory.
A second objection is that trials are expensive to run. Perhaps; although not as expensive as blundering around without a clue, and trials are often cheaper to run than one might think.
Policies are often rolled out gradually; if this gradual roll-out is randomised, drawing conclusions from the new policy becomes vastly simpler and more robust.
Perhaps the real problem is that too many politicians and civil servants have little knowledge of, or respect for, basic scientific methods. According to Mark Henderson, author of The Geek Manifesto, a mandarin at the Department for Work and Pensions once told Tony Blair’s chief scientific adviser that the DWP could function perfectly well without any contribution from science – a demonstration of grotesque ignorance and arrogance. Fortunately, as the new guide explains, the DWP is already benefiting from evidence gleaned from randomised trials.
What matters is what works, we have been told by generations of politicians. But finding out what works is a serious business. Perhaps, at last, it is also a business that Whitehall is taking seriously.
Also published at ft.com.





7 Comments
Stephen Henderson says:
It’s strange that you mention phonics as a candidate for RCT. A couple of years ago I went to one of the Intelligence-Squared open days in London. One of the debates was on teaching phonics. After hearing a lot of waffle from both sides a proponent and opponent (both professors of education if I recall correctly), the floor was opened for questions – and I asked precisely this point.
The major problem with evidence on phonics – or indeed most educational methods was that the trials such as they were usually involved highly motivated specialists picking a school and then unsurprisingly outperforming the national average school.
So I suggested that reasonable trial would be to field test it with real teachers in a selection of schools and compare the results to similar schools from the same area.
The reply to this was total evasion. The phonetics proponent said correctly that an educational trial couldn’t be blind – mumbled a bit about some other irrelevancies and then quickly moved on. I got the feeling they were embarrassed and didn’t want to address the question in front of an audience. Their whole demeanour was really odd so it sticks in my mind.
30th of June, 2012Aveek says:
Perhaps the resistance comes from the idea that things like children’s education are too important to experiment with – randomised trials are likely to investigate missteps and blind alleys, and for the people who get the wrong treatment, it is like they are being sacrificed in the name of progress.
A related point is that equality is a particularly strong consideration in matters like education – some people might feel it’s better to treat everybody the same, even if different treatments might give rise to better comprehensive policies in the future.
I’m not saying these are good arguments, just suggesting they might explain resistance to policy trials.
Then again, similar arguments could be raised against medical trials, I guess.
30th of June, 2012James Rae Smith says:
Sorry to be cynical, but given the record this (like most other) governments have of the deceptive and misleading use of what real data they have already to justify policy initiatives, what chances are there that the results of any trials will not be similarly misused. I am thinking particularly of David Cameron’s recent speech on welfare reform, and the government’s statements about “troubled families”. In both these cases they continue to make misleading claims, despite having their statistics rubbished by yourself and others. If something fits well with what the readers of the Daily Mail know is common sense, facts will often be twisted to fit prejudices.
30th of June, 2012Sumit says:
I’ve read the Ladybird book and enjoyed it. As a civil servant statistician I’m glad that there is another resource out there to demonstrate how to use statistical ideas to improve policy making. But I think the problem is a bit deeper to solve. After all there are thousands of civil servants from the statistics, social research, economics and science professions who must know about RCTs. The real question is how, despite this, the most influential decision makers don’t hear or pay heed to this advice. I don’t think the Ladybird book by itself will help much.
1st of July, 2012Laurence Moore says:
Further to Stephen Henderson’s post, the kind of randomised trial that he proposes, where the implementation of phonics occurs in schools randomised to phonics, with other schools randomised to another method, and in both schools the implementation occurs just as it would do in the real world, is definitely possible, and there are many examples where studies of this type have occurred, particulalry in health services and public health research. In such implementation trials, it is recognised that there will be variations in delivery, receipt, responsiveness, context, yet the trials will identify an unbiased estimate of the difference in outcomes between the two groups. And these trials can be very cheap – if routine data are available in all of the study schools to capture outcomes, then the costs are practically zero. Unfortunately, many of the most vociferous contributors to the debate on trials assume that a randomised trial is the kind of trial that requires highly standardised interventions, and with delivery optimised to the extent that it is usually undertaken by the researchers themselves or by highly trained educators. Such trials are known as efficacy trials, and can be important in identifying the efficacy and plausability of interventions, but do not really help us identify what the best policy options are. In the US, Kessler and Glasgow have called for a moratorium on the funding of efficacy trias, as they are of so little value to policy and practice http://www.ncbi.nlm.nih.gov/pubmed/21565657. A more sophisticated debate is needed!
3rd of July, 2012Stephen Henderson says:
@Aveek
As there is clear doubt whether phonics is the best approach it can’t be unethical to split pupils into phonics and non-phonics. We don’t know which group – if any – would be disadvantaged.
It is far more unethical to pick an intervention based on imperfect understanding and force it on everyone.
My own feeling is that if the benefit is so controversial it is quite likely that both methods work similarly well – so those in the ‘wrong’ arm of the trial will probably learn to read OK too. They won’t die or end up in jail.
4th of July, 2012Patrick says:
The author rightly criticises some poor criticisms of randomization for public policy: namely that it is too expensive or it is redundand as ‘we already know what works’. But I’d be interested to know what he makes of much sounder criticism of randomized controlled trial made by the likes of Angus Deaton at Princeton: http://www.princeton.edu/~deaton/downloads/Instruments_of_Development.pdf
6th of July, 2012And those by Dani Rodrik at Harvard: http://www.hks.harvard.edu/fs/drodrik/Research%20papers/The%20New%20Development%20Economics.pdf
Thanks
Patrick