Behavioural science — a catch-all term for a strand of psychology, with micro-economics, sociology and other disciplines mixed in — has been unusually prominent during the pandemic, and particularly so in the UK. For a while at the start of 2020, it was touted as the answer to all our prayers. “Nudges” to change people’s behaviours were suddenly the order of the day. “Behavioural science can”, we were assured, “save lives”; without it, “our attempts to defeat the virus will fail”. On the BMJ’s blog, UCL psychologist Susan Michie and her colleagues wrote a post entitled: “Behavioural science must be at the heart of the public health response to Covid-19”. Boris Johnson himself was directly advised by “behavioural psychologists”, and specifically referenced them at a press conference.

At the end of March, just after lockdown began, I wrote for UnHerd about the bad predictions and faulty logic of psychologists (and other people writing about risk). I argued that low-quality evidence was being relied on to support arguments that downplayed the danger of the disease. But the story of our Government’s engagement with behavioural science during this pandemic extends far beyond that. Now that a whole year has passed since the UK recorded its first Covid cases, it’s a good time to look back at what the much-lauded discipline contributed to our Covid response.

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Don’t trust the psychologists on coronavirus

By Stuart Ritchie

Behavioural science had great press for a few weeks, but it all fell apart pretty fast. As case numbers and deaths in the UK increased throughout March, many began to wonder why we weren’t following the example of other countries and locking down. The blame, according to some, lay at the feet of the behavioural scientists. Apparently, they’d advised the Government that the population would suffer “behavioural fatigue” — that after just a few weeks of strict lockdown measures, we’d get bored and frustrated, and start bending the rules in an attempt to get back to normal life.

Chief Medical Officer Chris Whitty, Deputy Chief Medical Officer Jenny Harries, Chief Scientific Adviser Patrick Vallance, and others all made this argument explicitly in the media. It would be counter-productive to go too hard too soon, they said. Such a huge change to people’s lives wouldn’t be sustainable, and people might make a collective break for freedom just as the virus was most prevalent.

But behavioural scientists, whose discipline was supposedly the basis of the Government’s policy, were outraged by this narrative. Michie, a member of the Government’s SAGE subcommittee on behavioural science, SPI-B, told the Guardian that the concept of “fatigue” had never been used in any of their reports (which was true). Indeed, she said, “[fatigue] is just not a concept that exists in behavioural science”. Warwick behavioural scientist Nick Chater agreed, writing that behavioural fatigue “has no basis in science”. Another member of SPI-B, Robert West, made much the same argument. An Open Letter from UK psychologists and behavioural scientists urged the Government to reveal the evidence base for the fatigue concept (I was among nearly 700 signatories).

As it turns out, there was evidence in the scientific literature for the idea of “behavioural fatigue” all along. The neuropsychologist Vaughan Bell, as far back as late March, reviewed a selection of papers (all published pre-2020) that discussed the fatigue idea in the context of people’s rule-compliance in past disease outbreaks, though they didn’t necessarily use the specific word “fatigue”. As Bell noted, some found evidence for it, some against — and the studies certainly weren’t all top-quality. But the idea spread by behavioural scientists before the first lockdown — that “behavioural fatigue” was a concept entirely divorced from the scientific literature — was flat wrong.

So far, so embarrassing: the psychologists either weren’t aware of the relevant evidence, or wanted to shift the blame for the delayed lockdown away from behavioural science (even though they’d never advocated for it). Whitty, Harries and Vallance, for their part, never pointed to any of the science they were relying on to make their claims. Confusion reigned. The lockdown was delayed on the basis of some unknown evidence. Behavioural science seemed to have failed its first and biggest test of the pandemic.

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The Government's Covid comms failure

By Dan Hitchens

To make things worse, the “fatigue” debate was essentially irrelevant to what the Government should have been doing in the face of the virus. Regardless of whether people’s compliance with the rules would decay over time, it would still have made sense to lock down earlier, because the virus spreads exponentially. Stopping it from taking hold early in an outbreak (a policy that worked in countries like New Zealand and Taiwan) means that the population — even if they start to break more rules as time goes on — will be at far less risk of the disease. To put it another way: despite the hype, the behavioural science should have been very much secondary, something to worry about only if a government fails to properly contain the spread of infection.

You’ll have noticed, of course, that our government did fail to properly contain the spread of infection. We didn’t lock down early enough — twice — and we’ve now had over 100,000 coronavirus deaths. So perhaps there’s more of a role for behavioural science now. But have we learned anything in the past year about how to mould human behaviour to keep people from Covid?

My behavioural scientist colleagues won’t like me for saying this, but the answer is: not really. A number of recent studies have explored how to improve interventions such as hand-washing, face-touching, mask-wearing, and vaccine-getting. (Let’s leave aside the awkward fact that the first two probably aren’t all that relevant to stopping the spread – the behavioural scientists weren’t to know that at the time.) These interventions are a smorgasbord of tricks to get people thinking differently about the virus: asking them to plan for the future; targeting their emotions; telling them how social distancing can save the economy; focusing them on reasoning rather than gut feelings; and so on — all things that might be adapted into government messaging, if they work.

But do they? Some of them, such as asking a person to write down the name of a loved-one they want to protect, have shown no effects whatsoever. Others, like focusing on moral messages, or those delivered by a respected figure, are supported by patchy evidence that shows generally small effects. Some have shown effects only in particular circumstances: one study tried a range of different interventions and found that some worked, but only for people who had just recently begun social distancing. For those who had been social distancing for longer, the interventions backfired — the participants reported going outside more and distancing less after they’d taken part in the intervention. Oops.

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It's not our job to protect the NHS

By Timandra Harkness

Even for the studies that appear more promising, one has to remember what’s actually being measured: in most cases, it’s people’s self-reported intentions to do things like wash their hands or wear masks. It’s what they tick on a questionnaire during the experiment — not necessarily what they’ll do in the real world. Of course, intentions and actions will be related to one another, but not perfectly. Researchers should be a lot more careful than the authors of the questionnaire study that appeared in September, whose very title claimed that “Empathy Promotes Physical Distancing and Wearing of Masks”. The only data they gathered concerned self-assessed motivations — not behaviours. “Intentional science” sounds somewhat less impressive than “behavioural science”, but it would, alas, be much more accurate.

Yet more evidence is appearing all the time: perhaps the behavioural scientists will crack a solid, reliable intervention soon. But the discipline’s contribution to the pandemic feels like a classic case of over-promising and under-delivering. The confident claims at the start of the pandemic — that behavioural science would play a crucial role in the Government’s toolkit to keep us all safe — simply fell flat when the actual data were examined. Had the hype been dialled back a little, behavioural science’s messy evidence base would look more like a discipline doing its best to find out what works (which is a genuinely difficult task), rather than a big disappointment.

Even if our ability to alter human behaviour using clever psychological techniques is weaker than we’d like, it is still useful for understanding human behaviour in the pandemic. To take just one example: knowing what people believe, and how those beliefs change over time, is important for governments and health systems to target their policies.

UCL’s Covid-19 Social Study is packed with interesting data on this topic. One of the overall findings is that people’s compliance with the rules (again, self-reported, so caveat emptor) has waxed and waned along with Covid cases: the recent second wave was accompanied by more people saying they follow all the rules. The main driver of people’s behaviour seems to be how many infections there are in the country (which ultimately depends on government policies like lockdown and border control); “soft” behavioural science interventions like nudges are only going to be useful at the margin.

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The Government's Covid comms failure

By Tom Chivers

To those new UK Government adverts, they seem to be an attempt to use a mixture of empathy, shame and fear to promote compliance. Although there’s plenty of evidence to show that the latter of these has worked in previous contexts, it’s hard to apply any previous research to our unprecedented situation. It certainly feels to me that more attention paid to actual Covid patients, rather than just graphs of case numbers, would jolt people out of complacency — but that’s the hunch of a behavioural scientist, rather than evidence from behavioural science.

And there’s nothing wrong in theory with a behavioural scientist giving you their opinion — if they’re clear that’s what it is. The superficially convincing sheen of “science” is too easily applied to what are often just thoughts and judgements by well-meaning, well-informed experts (or mostly well-informed: the “fatigue” debacle illustrates how even the experts can fail to be on top of their brief). Setting the behavioural scientists up as some kind of oracular group of truth-tellers who’ve figured out the intricacies of the human mind is setting them up for failure — and trivialising the very real contributions they can make.

So can I look you in the eyes and tell you that the new adverts will work? Not really. But what do I know? I’m just a behavioural scientist.

The question is not why the UK government originally adopted the 2 metre rule. Very little was known about Covid-19 when the pandemic first reached the UK, and 2 metres was the standard recommended distance for infectious diseases that seemed to spread through the air in droplets or a fine aerosol of fluids, inhaled or otherwise absorbed by the next victim. In a lockdown, and in the absence of any other evidence, why not adopt the standard?

The question is why, as new evidence emerged, Britain was so slow to follow France, Denmark, Singapore, Hong Kong, China and indeed the WHO in dropping the minimum recommended distance to just one metre? Emerging research suggested that Covid tends to travel by heavier, larger droplets. Physics, not biology, shows they fall to the ground rapidly, so the risk reduction of one metre separation is significant, but adding another metre has less impact. Some other countries decided to stay on the safe side with 1.5 metres, but the UK held out till this week at 6ft 6in.

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Coronavirus doesn't care about politics

By Freddie Sayers

Of course, the virus doesn’t follow rules. If somebody is infectious, there is no hard limit beyond which you are safe. And, since people can be infectious before showing any symptoms, anyone represents at least a theoretical risk of infection. We are looking at degrees of risk, and what measures we’re willing to take to reduce them. Outdoors is safer than indoors. Wearing a mask is safer than not. Facing the same way and talking like spies meeting on a park bench is safer than face to face. And all this is provisional, as we’re not putting patients in labs and letting them breathe on volunteers to find out.

It could just be that the British Government wanted to wait until the disease was less prevalent before letting us get a little closer. Or it could be the latest in a long history of telling us, not what the science says, but what the public health officials think we need to be told.

Take “5 a Day”, the guideline that tells us all to eat five portions of fruit and vegetables every day (potatoes don’t count, despite being so rich in Vitamin C that their introduction to Britain ended endemic scurvy). That has a number in, so surely it must be based on scientific research? Indeed, the NHS “Why  5 A Day?” page says the campaign is based on WHO advice to eat 400g of fruit and vegetables to lower the risk of heart disease, stroke and cancer.

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It's worth taking a risk over Covid-19

By Timandra Harkness

There is research linking more fruit and vegetables to lower risks of some diseases, but that’s not the origin of the campaign. In 1980s California, the state’s Department of Health Services found a happy harmony between the desire to improve public health through diet, and the economic benefit to the region’s farmers from increased sales. In the American Journal of Preventive Medicine, the Department’s then Director, Ken Kizer, summarised its success:

“The 5 a Day-for Better Health! Campaign had several distinctive features, including its simple, positive, behavior-specific message to eat 5 servings of fruits and vegetables every day as part of a low-fat, high fiber diet; its use of mass media; its partnership between the state health department and the produce and supermarket industries; and its extensive use of point-of-purchase messages.”

Professor Tim Lang was advising the UK government in the late 1990s when he was told of the US campaign and felt “we needed something”. Tony Blair’s Labour government was looking for specific policy targets, and five was “a nice round number”. The scientific precision of 400g was retrofitted later to give the “simple, positive, behaviour-specific message” more scientific authority.

Or take government guidelines for how much alcohol we should drink, revised in 2016 to “You are safest not to drink regularly more than 14 units per week.” This was cut down from the old guidelines, which were 14 units for women and 21 for men, recognising the differences in average physiology. They in turn were revised downwards in 1984 from 56 units per week, almost a bottle of wine per day. Our parents were made of sterner stuff.

But the new guidelines are based on better science, right?

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Do any Covid-19 'cures' actually work?

By Tom Chivers

Well, it depends what you mean by science. Like most public health questions, it would be unethical to apply randomised controlled trial methods to habits that you suspect are unhealthy. Nobody assigned human adults randomly to drink nearly a bottle of wine a day or no alcohol at all, and recorded their time and cause of death. Health advice is based on a mixture of ‘ecological’ observation (real humans drinking in the wild and then reporting their intake) and mathematical modelling.

The new guidelines took an extreme position on the protective effects of small amounts of alcohol (around a unit a day) against cardiovascular diseases, for which there is robust evidence. Light drinkers are around 20% less likely to die of anything in a given period than teetotallers, even excluding people who have stopped drinking because they’re ill.

Arguing that deaths from cardiovascular disease have fallen significantly, the Chief Medical Officers argued that this made the protective effect less important, and that it was only significant in women over 55. They may have based this on a paper published in the BMJ claiming that such benefits were limited to women over 65, a claim that the statistician Professor David Spiegelhalter described as misleading, commenting that “a more appropriate headline would have been ‘Study supports a moderate protective effect of alcohol’ … This is a poor use of statistics, and I am surprised it got past the referees and into the journal.”

The new, lower drinking guidelines are not a change in public message that reflects a change in scientific research. The research has been selected, or even commissioned, to justify new, lower guidelines. A more honest public health message would be: “Depending on who you are, a drink a day is probably good for you, and every subsequent drink increases your risk of illness and death”. But that would muddy the “simple, positive, behavior-specific message”.

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The danger of safetyism

By Matthew Crawford

Public health campaigns are, by nature, broad brush and aimed at mass populations. Most of us want rules of thumb, not scientific papers, when we’re weighing up what to eat, drink or smoke, whether to go for a run, how close to stand in the supermarket queue. We understand that advice is to be taken in context, not as a protective spell that will guard us from all harm.

In a pandemic, as new understanding emerges by the day, clarity is even more important. As early as February, scientific advice to the government about how to handle the Covid-19 pandemic included the importance of being clear and definitive, coherent and consistent, not only to improve compliance with helpful actions, but to discourage pointless or counterproductive ones.

But this is no excuse for dishonesty about the basis for official advice or rules. Where the scientific basis for policies was uncertain, it would have been far better to say that the science was uncertain, but the government had made a decision for these reasons: erring on the side of caution until more was known, or recognising that human life is about more than medical health.

When the WHO switched its advice to one metre, what was the rationale for sticking with two? Fear of looking indecisive? Lack of faith in British people to know what a metre looks like? In mid-March, the UK’s scientific advisory group, SAGE, was invoking behavioural science to argue that the public is mostly rational and altruistic in a crisis:

“The behavioural science points to openly explaining to the public where the greatest risks lie and what individuals can do to reduce their own risk … Greater transparency will help people understand personal risk and enable personal agency, send useful signals about risk in general and build public trust. Citizens should be treated as rational actors, capable of taking decisions for themselves and managing personal risk.”

Of all the expert advice given to the government, it’s a pity this paragraph has been so often ignored.