Table Summary of pitfalls in judgment Pattern Strategy Example Fear of the unknown Unknown risks attract more attention than do regular events Provide repeated reminders after the initial shock fades “We've been at it for a while, yet must be as vigilant as when it was all new.” Personal embarrassment Unintended personal lapses add to later self-blame or stigma Acknowledge that this reaction is normal behaviour and use celebrity patients to lessen stigma “This can happen to everybody. Tom Hanks acquired COVID-19 infection too.” Neglect of competing risk Prominent threats deflect attention from other risks Stay mindful of mundane everyday hazards that can be overlooked “This pandemic is not the only risk to your health that needs attention.” Invisible diseases Problems might be missed if objective data are absent Guard against mental health complications “Social distancing causes stress due to isolation. How are you coping?” No clear feedback Learning requires reliable follow-up Avoid scrutinising rapidly fluctuating and unstable updates “Focus on your own planned behaviour and not population statistics that change daily.” Status quo bias Strong desire to resist change Emphasise potential future gains “This crisis can help us to look at many things anew.” Ingrained societal norms Habits are difficult to change Keep reminding and highlighting others who have changed behaviours “Remember to avoid touching your face and politely correct those still doing it.” Hindsight bias Summary judgments are weighed by final outcomes Avoid second guessing early attempts too harshly “The pandemic was hard to predict and difficult to manage at the time.” The coronavirus disease 2019 (COVID-19) crisis is a pandemic challenging human biology, the capacity of acute care hospitals, the financial resilience of economies, and the communication network for people. Strategies for reducing transmission have included repeated hand washing, physical distancing, and self-isolation. These preventive strategies are immediately available, highly affordable, and distinctly effective; however, a major challenge is the need to maintain adherence. The purpose of this Comment is to review eight behavioural pitfalls reported by psychological science, which are relevant to contexts that require judgment under uncertainty ( table ). We suggest that awareness of these pitfalls might help to maintain behaviour change to fight the COVID-19 crisis.

1 Slovic P Perception of risk. 2 Gorka SM

Lieberman L

Shankman S

Phan KL Startle potentiation to uncertain threat as a psychophysiological indicator of fear-based psychopathology: an examination across multiple internalizing disorders. 3 Hamzelou J Mysterious illness outbreak in China seems to be caused by a new virus. The first pitfall is fear of the unknown. A traditional factor attracting attention is the psychological response to threats that are mysterious.Such intense sensitivity to uncertain threats—a hypervigilant fear of the unknown—is common and often at the root of fear-based psychopathologies.COVID-19 was initially denoted as the coronavirus of unknown origin, raising a particularly ominous spectre of unseen troubles.However, with time the relative newness and mystery of COVID-19 will fade, leading to a commensurate reduction in attention. Adaptation to familiar circumstances means the sense of threat will attenuate, along with adherence to public health recommendations. Repeated creative reminders linked to the evolving situation are important to avoid complacency as people grow inured.

4 Redelmeier DA

Shafir E Why even good physicians do not wash their hands. The second pitfall is personal embarrassment. One preventive strategy for COVID-19 is to avoid self-touching behaviours, such as placing a hand on the face. This recommendation is sensible because viral infection requires contact with a mucous membrane. A difficulty arises, however, because people have endless reflexive habitual actions that are hard to suppress.A lapse can be construed as a personal failure that is visible to others and causes shame. Furthermore, a subsequent infection connected to a preceding lapse might add to self-blame. Opinion leaders can highlight one of many celebrities who have tested positive as a way of mitigating the stigma. Additionally, authorities should counsel that momentary lapses are entirely natural, often surmountable, and should be followed by returning to best behaviours.

5 Redelmeier DA

Tan SH

Booth GL The treatment of unrelated disorders in patients with chronic medical diseases. The third pitfall is neglect of competing risks. COVID-19 is an overwhelming preoccupation. People particularly tend to focus their full attention on the threat, thereby causing tunnel vision that makes it easy to neglect a multitude of less salient considerations.Ongoing sleep, regular exercise, and human companionship all merit continued attention, which is contrary to an overwhelming sense that all else can wait. One way to address this challenge is by collaborating with clinicians to maintain a patient's context and to encourage in ways that promote safety against other harms. Individual patients still need to manage chronic diseases properly through continued adherence with medications, diet, and follow-up care. Keeping track of secondary hazards stays important, even in a pandemic.

Another pitfall is invisible diseases. COVID-19 receives attention partially because it has an objective test that establishes the diagnosis. By contrast, most mental health disorders cannot be tracked with a test or tangible sign. The physical distancing recommended for COVID-19 also carries a downside of potentially increasing domestic frictions due to home isolation for some people or increased home interactions for others. This situation can potentially exacerbate a chronic psychiatric disorder (eg, paranoid schizophrenia, major depression, substance abuse) in conjunction with decreased access to psychiatric care. Increased mental health care and communication, supportive of a healthy home environment, are warranted for consistent behaviour change.

6 Skinner BF Are theories of learning necessary?. An additional pitfall is that no clear feedback is provided. COVID-19 is unsettling because of the long incubation period, including a protracted wait between implementing an intervention and finding out results. These features are the antithesis of reinforcing positive behaviour through prompt unambiguous feedback.The time delay also leads to an unnerving interval marked by psychosomatic symptoms and a sense of impending doom in earlier stages of the crisis. These vexing emotions are inevitable when a risk has widespread importance, yet slow onset. Furthermore, feelings will probably fluctuate in later stages because of difficulties in recognising a false finish or a second wave. Authorities should urge caution against acting on daily epidemic reports because random volatility might be mistaken for a real trend.

7 Tversky A

Kahneman D Loss aversion in riskless choice: a reference-dependent model. A further pitfall is that a status quo bias abounds. Human behaviour is driven by a strong aversion to losses and a desire to maintain the status quo, which is an impulse that favours recouping losses rather than seizing options that lead to superior outcomes.Therefore, a temporary shaking of the status quo is an opportunity to refocus and look at things anew. Once the initial urgency is diminished, for example, hospitals can reconsider how clinicians adapt to new forms of telemedicine. A more radical suggestion could revisit the broader policy debates on whether nations without universal health care might return to a new normal. In general, some important public health advances might be easier to implement during an epidemic than before its onset or once the epidemic has largely abated.

8 Thaler RH

Sunstein CR Nudge: improving decisions about health, wealth, and happiness. Ingrained societal norms are another pitfall. Human behaviour is heavily influenced by deeply ingrained societal norms. Welcoming patients warmly, standing close to colleagues, dining together with friends, and caring for grandparents are all behaviours that have been promoted and polished over a lifetime. Such norms are not easy to change.Broadcasting and reminding patients about changed norms through slogans, images, and personal examples can help to facilitate the necessary behaviour change. Doctors and nurses are respected members in the community and need to be both transmitters of good information and role models for the right norms in and out of hospital. This approach might also help counteract misinformation that can circulate through internet sources.

Hindsight bias is the final pitfall. The COVID-19 pandemic will eventually subside. At that point, hindsight bias will lead to castigating medical authorities who might have over-reacted or under-reacted (potentially exacerbated by adversarial political accusations of incompetence). The uneven distribution of cases within and between countries will further lead to charges of inequality and injustice. Needless to say, some of the critiques will be correct and justified. Dynamic and contradictory data, however, might make it difficult to establish exactly what was known at what time, and how differently things could have turned out otherwise. The collective mentality that we are all in this together was challenging when the COVID-19 pandemic began and might prove as equally difficult to sustain after it is over. Awareness of judgmental pitfalls might help to make things a little easier.

We declare no competing interests.

We thank Fizza Manzoor (University of Toronto, ON, Canada) and Sheharyar Raza (University of Toronto, ON, Canada) for their helpful comments.