Do we suffer ‘behavioural fatigue’ for pandemic prevention measures?

The Guardian recently published an article saying “People won’t get ‘tired’ of social distancing – and it’s unscientific to suggest otherwise”. “Behavioural fatigue” the piece said, “has no basis in science”.

‘Behavioural fatigue’ became a hot topic because it was part of the UK Government’s justification for delaying the introduction of stricter public health measures. They quickly reversed this position and we’re now in the “empty streets” stage of infection control.

But it’s an important topic and is relevant to all of us as we try to maintain important behavioural changes that benefit others.

For me, one key point is that, actually, there are many relevant scientific studies that tackle this. And I have to say, I’m a little disappointed that there were some public pronouncements that ‘there is no evidence’ in the mainstream media without anyone making the effort to seek it out.

The reaction to epidemics has actually been quite well studied although it’s not clear that ‘fatigue’ is the right way of understanding any potential decline in people’s compliance. This phrase doesn’t seem to be used in the medical literature in this context and it may well have been simply a convenient, albeit confusing, metaphor for ‘decline’ used in interviews.

In fact, most studies of changes in compliance focus on the effect of changing risk perception, and it turns out that this often poorly tracks the actual risk. Below is a graph from a recent paper illustrating a widely used model of how risk perception tracks epidemics.

Notably, this model was first published in the 1990s based on data available even then. It suggests that increases in risk tend to make us over-estimate the danger, particularly for surprising events, but then as the risk objectively increases we start to get used to living in the ‘new normal’ and our perception of risk decreases, sometimes unhelpfully so.

What this doesn’t tell us is whether people’s behaviour changes over time. However, lots of studies have been done since then, including on the 2009 H1N1 flu pandemic – where a lot of this research was conducted.

To cut a long story short, many, but not all, of these studies find that people tend to reduce their use of at least some preventative measures (like hand washing, social distancing) as the epidemic increases, and this has been looked at in various ways.

When asking people to report their own behaviours, several studies found evidence for a reduction in at least some preventative measures (usually alongside evidence for good compliance with others).

This was found was found in one study in Italy, two studies in Hong Kong, and one study in Malaysia.

In Holland during the 2006 bird flu outbreak, one study did seven follow-ups and found a fluctuating pattern of compliance with prevention measures. People ramped up their prevention efforts, then their was a dip, then they increased again.

Some studies have looked for objective evidence of behaviour change and one of the most interesting looked at changes in social distancing during the 2009 outbreak in Mexico by measuring television viewing as a proxy for time spent in the home. This study found that, consistent with an increase in social distancing at the beginning of the outbreak, television viewing greatly increased, but as time went on, and the outbreak grew, television viewing dropped. To try and double-check their conclusions, they showed that television viewing predicted infection rates.

One study looked at airline passengers’ missed flights during the 2009 outbreak – given that flying with a bunch of people in an enclosed space is likely to spread flu. There was a massive spike of missed flights at the beginning of the pandemic but this quickly dropped off as the infection rate climbed, although later, missed flights did begin to track infection rates more closely.

There are also some relevant qualitative studies. These are where people are free-form interviewed and the themes of what they say are reported. These studies reported that people resist some behavioural measures during outbreaks as they increasingly start to conflict with family demands, economic pressures, and so on.

Rather than measuring people’s compliance with health behaviours, several studies looked at how epidemics change and used mathematical models to test out ideas about what could account for their course.

One well recognised finding is that epidemics often come in waves. A surge, a quieter period, a surge, a quieter period, and so on.

Several mathematical modelling studies have suggested that people’s declining compliance with preventative measures could account for this. This has been found with simulated epidemics but also when looking at real data, such as that from the 1918 flu pandemic. The 1918 epidemic was an interesting example because there was no vaccine and so behavioural changes were pretty much the only preventative measure.

And some studies showed no evidence of ‘behavioural fatigue’ at all.

One study in the Netherlands showed a stable increase in people taking preventative measures with no evidence of decline at any point.

Another study conducted in Beijing found that people tended to maintain compliance with low effort measures (ventilating rooms, catching coughs and sneezes, washing hands) and tended to increase the level of high effort measures (stockpiling, buying face masks).

This improved compliance was also seen in a study that looked at an outbreak of the mosquito-borne disease chikungunya.

This is not meant to be a complete review of these studies (do add any others below) but I’m presenting them here to show that actually, there is lots of relevant evidence about ‘behavioural fatigue’ despite the fact that mainstream articles can get published by people declaring it ‘has no basis in science’.

In fact, this topic is almost a sub-field in some disciplines. Epidemiologists have been trying to incorporate behavioural dynamics into their models. Economists have been trying to model the ‘prevalence elasticity’ of preventative behaviours as epidemics progress. Game theorists have been creating models of behaviour change in terms of individuals’ strategic decision-making.

The lessons here are two fold I think.

The first is for scientists to be cautious when taking public positions. This is particularly important in times of crisis. Most scientific fields are complex and can be opaque even to other scientists in closely related fields. Your voice has influence so please consider (and indeed research) what you say.

The second is for all of us. We are currently in the middle of a pandemic and we have been asked to take essential measures.

In past pandemics, people started to drop their life-saving behavioural changes as the risk seemed to become routine, even as the actual danger increased.

This is not inevitable, because in some places, and in some outbreaks, people managed to stick with them.

We can be like the folks who stuck with these strange new rituals, who didn’t let their guard down, and who saved the lives of countless people they never met.

The Choice Engine

A project I’ve been working on a for a long time has just launched:

By talking to the @ChoiceEngine twitter-bot you can navigate an essay about choice, complexity and the nature of our minds. Along the way I argue why the most famous experiment on the neuroscience of free will doesn’t really tell us much, and discuss the wasp which made Darwin lose his faith in a benevolent god. And there’s this animated gif:

Follow and tweet START @ChoiceEngine to begin

After the methods crisis, the theory crisis

This thread started by Ekaterina Damer has prompted many recommendations from psychologists on twitter.

Here are most of the recommendations, with their recommender in brackets. I haven’t read these, but wanted to collate them in one place. Comments are open if you have your own suggestions.

(Iris van Rooij)
“How does it work?” vs. “What are the laws?” Two conceptions of psychological explanation. Robert Cummins

(Ed Orehek)
Theory Construction in Social Personality Psychology: Personal Experiences and Lessons Learned: A Special Issue of Personality and Social Psychology Review

(Djouria Ghilani)
Personal Reflections on Theory and Psychology
Gerd Gigerenzer,

Selected Works of Barry N. Markovsky

(pretty much everyone, but Tal Yarkoni put it like this)
“Meehl said most of what there is to say about this”

  • Theory-testing in psychology and physics: A methodological paradox
  • Appraising and amending theories: The strategy of Lakatosian defense and two principles that warrant it
  • Why summaries of research on psychological theories are often uninterpretable
  • (Which reminds me, PsychBrief has been reading Meehl and provides extensive summaries here: Paul Meehl on philosophy of science: video lectures and papers)

    (Burak Tunca)
    What Theory is Not by Robert I. Sutton & Barry M. Staw

    (Joshua Skewes)
    Valerie Gray Hardcastle’s “How to build a theory in cognitive science”.

    (Randy McCarthy)
    Chapter 1 of Gawronski, B., & Bodenhausen, G. V. (2015). Theory and explanation in social psychology. Guilford Publications.

    (Kimberly Quinn)
    McGuire, W. J. (1997). Creative hypothesis generating in psychology: Some useful heuristics. Annual review of psychology, 48(1), 1-30.

    (Daniël Lakens)
    Jaccard, J., & Jacoby, J. (2010). Theory Construction and Model-building Skills: A Practical Guide for Social Scientists. Guilford Press.

    Fiedler, K. (2004). Tools, toys, truisms, and theories: Some thoughts on the creative cycle of theory formation. Personality and Social Psychology Review, 8(2), 123–131.

    (Tom Stafford)
    Roberts and Pashler (2000). How persuasive is a good fit? A comment on theory testing

    From the discussion it is clear that the theory crisis will be every bit as rich and full of dissent as the methods crisis.

    Updates 16 August 2018

    (Richard Prather)
    Simmering et al (2010). To Model or Not to Model? A Dialogue on the Role of Computational Modeling in Developmental Science

    (Brett Buttliere: we made a Facebook group to talk about theory)
    Psychological Theory Discussion Group

    (Eric Morris)
    Wilson, K. G. (2001). Some notes on theoretical constructs: types and validation from a contextual behavioral perspective

    (Michael P. Grosz)
    Theoretical Amnesia by Denny Borsboom

    (Ivan Grahek)
    Fiedler (2017). What Constitutes Strong Psychological Science? The (Neglected) Role of Diagnosticity and A Priori Theorizing

    (Iris van Rooij)
    More suggestions in these two theads (one, two)

    Open Science Essentials: Preprints

    Open science essentials in 2 minutes, part 4

    Before a research article is published in a journal you can make it freely available for anyone to read. You could do this on your own website, but you can also do it on a preprint server, such as psyarxiv.com, where other researchers also share their preprints, which is supported by the OSF so will be around for a while, and which allows you to find others’ research easily.

    Preprint servers have been used for decades in physics, but are now becoming more common across academia. Preprints allow rapid dissemination of your research, which is especially important for early career researchers. Preprints can be cited and indexing services like Google Scholar will join your preprint citations with the record of your eventual journal publication.

    Preprints also mean that work can be reviewed (and errors-caught) before final publication.

    What happens when my paper is published?

    Your work is still available in preprint form, which means that there is a non-paywalled version and so more people will read and cite it. If you upload a version of the manuscript after it has been accepted for publication that is called a post-print.

    What about copyright?

    Mostly journals own the formatted, typeset version of your published manuscript. This is why you often aren’t allowed to upload the PDF of this to your own website or a preprint server, but there’s nothing stopping you uploading a version with the same text (so the formatting will be different, but the information is the same).

    Will journals refuse my paper if it is already “published” via a preprint?

    Most journals allow, or even encourage preprints. A diminishing minority don’t. If you’re interested you can search for specific journal policies here.

    Will I get scooped?

    Preprints allow you to timestamp your work before publication, so they can act to establish priority on a findings which is protection against being scooped. Of course, if you have a project where you don’t want to let anyone know you are working in that area until you’re published, preprints may not be suitable.

    When should I upload a preprint?

    Upload a preprint at the point of submission to a journal, and for each further submission and upon acceptance (making it a postprint).

    What’s to stop people uploading rubbish to a preprint server?

    There’s nothing to stop this, but since your reputation for doing quality work is one of the most important things a scholar has I don’t recommend it.

    Useful links:

    Part of a series:

    1. Pre-registration
    2. The Open Science Framework
    3. Reproducibility

    Believing everyone else is wrong is a danger sign

    I have a guest post for the Research Digest, snappily titled ‘People who think their opinions are superior to others are most prone to overestimating their relevant knowledge and ignoring chances to learn more‘. The paper I review is about the so-called “belief superiority” effect, which is defined by thinking that your views are better than other people’s (i.e. not just that you are right, but that other people are wrong). The finding that people who have belief superiority are more likely to overestimate their knowledge is a twist on the famous Dunning-Kruger phenomenon, but showing that it isn’t just ignorance that predicts overconfidence, but also the specific belief that everyone else has mistaken beliefs.

    Here’s the first lines of the Research Digest piece:

    We all know someone who is convinced their opinion is better than everyone else’s on a topic – perhaps, even, that it is the only correct opinion to have. Maybe, on some topics, you are that person. No psychologist would be surprised that people who are convinced their beliefs are superior think they are better informed than others, but this fact leads to a follow on question: are people actually better informed on the topics for which they are convinced their opinion is superior? This is what Michael Hall and Kaitlin Raimi set out to check in a series of experiments in the Journal of Experimental Social Psychology.

    Read more here: ‘People who think their opinions are superior to others are most prone to overestimating their relevant knowledge and ignoring chances to learn more

     

    Review: John Bargh’s “Before You Know It”

    I have a review of John Bargh’s new book “Before You Know It: The Unconscious Reasons We Do What We Do” in this month’s Psychologist magazine. You can read the review in print (or online here) but the magazine could only fit in 250 words, and I originally wrote closer to 700. I’ll put the full, unedited, review below at the end of this post.

    John Bargh is one of the world’s most celebrated social psychologists, and has made his name with creative experiments supposedly demonstrating the nature of our unconscious minds. His work, and style of work, has been directly or implicitly criticised during the so-called replication crisis in psychology (example), so I approached a book length treatment of his ideas with interest, and in anticipation of how he’d respond to his critics.

    Full disclosure: I’ve previously argued that Bargh’s definition of ‘unconscious’ is theoretically incoherent, rather than merely empirically unreliable, so my prior expectations for his book are probably best classified as ‘skeptical’. I did get a free copy though, which always puts me in a good mood.

    If you like short and sweet, please pay The Psychologist a visit for the short review. If you’ve patience for more of me (and John Bargh), read on….

    Continue reading “Review: John Bargh’s “Before You Know It””

    Did the Victorians have faster reactions?

    Psychologists have been measuring reaction times since before psychology existed, and they are still a staple of cognitive psychology experiments today. Typically psychologists look for a difference in the time it takes participants to respond to stimuli under different conditions as evidence of differences in how cognitive processing occurs in those conditions.

    Galton, the famous eugenicist and statistician, collected a large data set (n=3410) of so called ‘simple reaction times’ in the last years of the 19th century.  Galton’s interest was rather different from most modern psychologists – he was interested in measures of reaction time as a indicator of individual differences. Galton’s theory was that differences in processing speed might underlie differences in intelligence, and maybe those differences could be efficiently assessed by recording people’s reaction times.

    Galton’s data creates an interesting opportunity – are people today, over 100 years later, faster or slower than Galton’s participants? If you believe Galton’s theory, the answer wouldn’t just tell you if you would be likely to win in a quick-draw  contest with a Victorian gunslinger, it could also provide an insight into generational changes in cognitive function more broadly.

    Reaction time [RT] data provides an interesting counterpoint to the most famous historical change in cognitive function – the generation on generation increase in IQ scores, known as the Flynn Effect. The Flynn Effect surprises two kinds of people – those who look at “kids today” and know by instinct that they are less polite, less intelligent and less disciplined their own generation (this has been documented in every generation back to at least Ancient Greece), and those who look at kids today and know by prior theoretical commitments that each generation should be dumber than the previous (because more intelligent people have fewer children, is the idea).

    Whilst the Flynn Effect contradicts the idea that people are getting dumber, some hope does seem to lie in the reaction time data. Maybe Victorian participants really did have faster reaction times! Several research papers  (1, 2) have tried to compare Galton’s results to more modern studies, some of which tried to use the the same apparatus as well as the same method of measurement. Here’s Silverman (2010):

    the RTs obtained by young adults in 14 studies published from 1941 on were compared with the RTs obtained by young adults in a study conducted by Galton in the late 1800s. With one exception, the newer studies obtained RTs longer than those obtained by Galton. The possibility that these differences in results are due to faulty timing instruments is considered but deemed unlikely.
    Woodley et al (2015) have a helpful graph (Galton’s result shown on the bottom left):
    (Woodley et al, 2015, Figure 1, “Secular SRT slowing across four large, representative studies from the UK spanning a century. Bubble-size is proportional to sample size. Combined N = 6622.”)

    So the difference is only ~20 milliseconds (i.e. one fiftieth of a second) over 100 years, but in reaction time terms that’s a hefty chunk – it means modern participants are about 10% slower!

    What are we to make of this? Normally we wouldn’t put much weight on a single study, even one with 3000 participants, but there aren’t many alternatives. It isn’t as if we can have access to young adults born in the 19th century to check if the result replicates. It’s a shame there aren’t more intervening studies, so we could test the reasonable prediction that participants in the 1930s should be about halfway between the Victorian and modern participants.

    And, even if we believe this datum, what does it mean? A genuine decline in cognitive capacity? Excess cognitive load on other functions? Motivational changes? Changes in how experiments are run or approached by participants? I’m not giving up on the kids just yet.

    References: