Aug 19 2016

Communicating Risk and Certainty

climate-change-denialA recent article in the Guardian discusses how scientists and experts should communicate risk and certainty to the public. The author, Jack Stilgoe, makes some good points, but unfortunately frames it as part of a defense of Jill Stein:

She said that there were ‘real questions’ about the dangers of vaccines, that GM foods have ‘not been proven safe’ and that ‘more more research is needed’ on the risks of electromagnetic fields.

As with climate change, it is tempting to claim that the science is certain, the evidence is clear and the debate should move on. Things are rarely so black-and-white. In politics, the facts don’t speak for themselves, so it falls to experts to make sense of the shades of grey.

Stilgoe is speaking of a dilemma faced by experts and science communicators when dealing with political or ideological opinions that diverge from the scientific consensus. The real dilemma is that if we communicate the science in technically accurate detail, it seems as if we are equivocating and those on the anti-science side will unfairly exploit this to exaggerate the uncertainty. If we gloss over the uncertainty to emphasize the bottom line, then the anti-science side will unfairly exploit that to say we are engaged in a cover-up and are being uncritical.

It is a no-win scenario, which is often the case when dealing with those who put ideology above science and reason. They aren’t playing fair, which can give them a rhetorical advantage over someone honestly trying to be fair.

It is also a lot easier to create and exploit doubt and confusion, than to give a thorough understanding of a complex topic.

Stilgoe concludes:

Expert groups are often relied upon by politicians to tidy up the facts on contentious issues. It rarely works. People don’t like being patronised with easy answers where there are none to find. With mobile phones, a group of experts took a different approach. They instead admitted that there are uncertainties and trusted in citizens’ ability to navigate them. When it comes to climate change, Wi-Fi, GM crops, vaccines and mobile phones, there will always be scientific grey areas. If experts want to regain their credibility, they urgently need to find ways to talk about them.

I agree with this basic approach, but would emphasize different points. I also seem to disagree with him regarding how uncertain we are about the topics he uses as examples.

The solution to the dilemma, in my opinion, is that the scientific community, science communicators, journalists, and government experts need to develop a common language with the public for communicating about risk. Right now there is confusion.

For example, Stilgoe writes:

In 2011, the International Agency for Research on Cancer classified mobile phone EMFs as a ‘possible human carcinogen’ (placing them alongside bacon and almost every other enjoyable food).

What does “possible human carcinogen” actually mean in terms of the scientific evidence? The IARC even admits:

Perhaps not surprisingly, based on how hard it can be to test these candidate carcinogens, most are listed as being of probable, possible, or unknown risk. Only a little over 100 are classified as “carcinogenic to humans.”

Even worse, the classification says nothing about dose. To get a good idea of how confusing, even to the point of being worthless in terms of public communication, just follow the link above to the list of known and probable carcinogens. Alcohol is a known carcinogen, yet people consume it on a regular basis without fear. Formaldehyde is also listed, without noting dose. There is natural formaldehyde in our bodies, and in many foods we eat. It is often pointed out that pears have more formaldehyde in them than vaccines, but the fact that this is listed as a known carcinogen is great fodder for anti-vaccine fear mongering.

Hot beverages and red meat are also listed. If you go down to “possible carcinogen” then you start to include things like caffeine.

This categorization may accurately reflect the scientific research in some way, but it does not communicate useful information to the public. In fact, it creates confusion. It doesn’t tell people how to stay healthy or minimize their risk.

We live in a complex world and are generally overwhelmed with information. What people want and need is an “executive summary” – what’s the bottom line? What people want to know are categories like: tiny theoretical risk, don’t worry about it; safe for everyday use; minimize exposure at all costs; safe in small doses but avoid excess, etc.

This goes beyond safety and carcinogens, of course. For climate change, for example, of course we are not 100% certain, the science is not over, there are unanswered questions and remaining uncertainty. There always will be. But the bottom line is – there is a solid scientific consensus that burning fossil fuels is warming the climate with potentially costly and unwanted (possibly even catastrophic) outcomes. If we want to avoid these probable outcomes we will need to start reducing our overall CO2 release now.

With vaccines the bottom line is – vaccines have a long history of both scientific evidence and clinical use demonstrating that they provide orders of magnitude more benefit than risk. There is no credible link to autism, and serious negative outcomes are extremely rare. Seriously, getting vaccinated is a no-brainer positive health intervention. (You may notice the difference between this and Jill Stein’s bottom line that “real questions” remain about the safety of vaccines.)

You can give an accurate overview of the science of a technology or substance without using unjustified words or phrases, like the “science is settled” or “zero risk.” Even if you think saying something like the “science is settled” is justified, that phrase is now a dog whistle to science deniers and is therefore counterproductive.

Make no mistake, effectively communicating science like this is very tricky, and it is a two-way street. I try to be as careful as I can be in discussing these controversial topics, and accurately reflecting the science while simultaneously communicating the proper bottom line. This often means putting things into their proper context.

I don’t think there is any one algorithm for communicating science that cuts through all the complexity. However, in certain situations when classification systems are used, they should be crafted with meaningful communication in mind. The “probable” or “possible” carcinogen categorization, in my opinion, is horrible and generates tremendous confusion and potential for anti-science exploitation.

Regarding Stilgoe’s article, he failed, in my opinion, to defend Stein’s statements. Just because the science is not absolute, because it is never absolute, that does not mean Stein’s exploitation of the usual scientific uncertainty was justified or appropriate. She pandered to the anti-vaccine, anti-GMO, and anti-technology crowd with phrases meant to convey sympathy to their anti-science positions.

She was exploiting scientific complexity and poor communication for ideological purposes.



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