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Rapport 1: leaving the number "4"

Specific question
The reason to call upon the expert opinion of psychological behavioural scientists was double:

  • How do we formulate exactly that we are leaving the number "4" for private contacts

  • What do we install instead to still reduce the risks?


Following up measures required an extraordinary effort of the population. The measures created a breach on our day to day lifestyle and we need to comply with them for a long period of time. At first, these measures seemed temporarilly, but now it's becoming clear that we are evolving towards a phase of permanent behavioural change. Behavioural change thus needs to lead to habit behaviour. Behaviour change mainly originates through frequent repetition, through which it is differently steered by our brain compared to conscient controlled behaviour: it's no more being consciently done to achieve a goal and it mainly runs automatically or without thought. To facilitate this kind of habit behaviour five pillars are important:

Core principles

  • A clear mental model: Accurate knowledge about the virus and the necessary behaviour to contain its spread and to avoid a new contamination wave is important. This knowledge needs to lead to a clear mental model that can be easily activated. The use of appealing "visuals" is therefore highly recommendable as a form of efficient knowledge transfer. Be mindful: approximately 10 % of the population is facing poor "health literacy": they are insufficiently reached by mainstream information channels - newspapers, TV - and have insufficient competency to understand and apply health information. They need to be adressed through different channels and in a moderated way.

  • Self - efficacy: Knowledge is a necessary but insufficient condition for behavioural change. Citizens kan know what is necessary (eg. to avoid contact), but they also need to feel competent to pose the required behaviour. If the measures are too hard or too complicated, then citizins will begin to doubt if they can pose or keep on posing the required behaviour. Even if the different measures are achievable seperatedly, many citizens may doubt their ability to bring all the measures as a whole into practice in a sustainable manner. Clear instructions, trust, positive role models, posing realistic intermediate goals and stimulating feedback can enhance this feeling of self - efficacy.

  • Voluntary responsability: Besides knowledge and competency a feeling of ownership is needed so that citizens can take up voluntary responsability for their behaviour. People who are convinced of the necessity and the importance of the measures and its goals will choose voluntary for the required behaviour. They show high levels of "commitment" so that they will commit themselves in a sustainable manner to live up to the measures, even when this becomes harder. The voluntary commitment to live up to the measures has steadily dropped since the beginning of the lock down: 80% of the population was voluntarily motivated at the beginning of the lockdown, today this is only 50 %. The "must"-ivation to live up to the measures is on the contrary risen. If the latter perceveires, then citizens will act more according to selfinterest and will look for the "holes" in the measures. Voluntary motivation is stimulated by adressing the "why" (the basis principles of the measures), to involve sectors in a participative manner and letting them fill in the required behaviour, be emphatically acknowledge barrieres/resistance and by generating transparency about the arguments and conditions to loosen or tighten the measures.

  • Unifying project: People are social beings: the like to belong to a group, they are highly sensitive for social appreciation/disapproval and they are inspired by social models. Creating habits within a group will be facilitated if the power of the group is maximally mobilised. This can be done by emphasizing the common goal, by stimulating reciprocal solidarity, installing new, unifying rituals (eg, applauding publicly), the deployment of social rolemodels/ influencers and by showing fellow people from different layers of the population to whom citizens can relate to and who thestify about their corona experiences, their motivation to live up to the measures and the way they do it. By creating a recruting mediacampagn the desired exemplary behaviour is quickly shared and mirrored. If the population can identify itself with a common group goal the (co-) ownership of the measures is stimulated.

  • Nudging: Behavioural change evolves to habit behaviours through context related support. In the case of nudging the context is created in such a way that desired behaviour is elicited and undesired behaviour is complicated (eg. the circulation arrows in a supermarket). Thanks to nudging the desired behaviour is activated without the citizen necessarily being aware of it. Implemenation of this is preferentially being done by systematic steering and guidance by experts.


The "disgraced rule of 4"

In Belgium up untill now social contacts are limited to "4 contacts". To formulate a meaningful alternative to the "disgraced rule of 4'" we propose 7 steps.

  • Introduce a psychological breach (Step 1): Announce a new phase, but not without looking back.

    • Looking back: “we have accomplished a lot" (= source of appreciation and proudness); “it has cost us a lot" (=recognition of the suffering and the efforts); “we are grateful for the cooperation of the population" we zijn dankbaar voor de medewerking van de bevolking” (=positive reinforcement of commitment).

    • Look ahead: The new goal is to (1) preserve what we have accomplished and to furter reinforce it; and (2) to restart life without (too much) risk for resurgence.

Recommendation: This looking back is a testimony of empathy and appreciation of the efforts made. Try to make this as concrete as possible and to personalize it as to reinforce the authenticity of the message.

  • Saying goodbye to "rules" (Step 2): Recognising that the "rule of 4" wasn't the most appropriate rule because the underlying logic wasn't clear. This has lead to personal interpretation of it and/or distancing oneself the measure.

Recommendation: Dare to show yourself vulnerable; progessing insights lead to correcting the measures.

  • Introduce the notion of "principle" (Step 3): Propose the "bubble principle" as the core principle (- philosophy). Do not speak of rules anymore but speak of principles. Principles refer to a logic and contain a higher degree of flexibility compared to rules. Principles incite reflection by which the population receives a limited space to fill it in themselves. This will stimulate the feeling of ownership and responsability.

Recommendation: Inform extensively the choice of the term "principle". Make an appeal on commitment to fill in the principles responsably.


  • Explanation bubble principle (Step 4) :

    • What: Inform in a understandable way what a bubble is and which other behaviour forms are acceptable amongs "bubblers" (people in the bubble), and how they are different from the common measures. Do these measures apply for all "bubblers" (adults and children) or are they limited to the interactions between specific age groups?

    • Why: Adress in a clear, simple way why this bubble principle is crucial. Give examples of wise and unwise applications of the bubble principle. Through visuals for instance it can be explained what the consequences are for opening up your own bubble to 1, 4 or 8 other bubbles.

    • Number: Formulate after this explanation a recommendation for the number of bubbles that can be opened. Align this recommendation very well with the reopening of the schools where a lot of bubbles are being opened up for children. (Possibly, one could speak of a "fist rule": this term also implies flexilibity, but contains the element of "rule" what is less recommendable).

    • Which: Encourage the population to be selective in their choice of bubbles they wish to meet frequently. A good "bubble click" is more important for the well being then the number of bubbles.

Recommendation: Use visuals to explain this in a comprehensive way.

  • Explanation combination with Testing & Tracing (Step 5):

    • Bubbling only works well in combination with a Testing and Tracing (T&T). They are
      2 cohered strategies:
      (1) Bubble strategy as a principle to limit the risk of spreading;
      (2) Testing and Tracing (T&T) to quickly trace and isolate contamination.

    • Ask a commitment to combine the "bubble" - strategy wih "testing & tracing" and to report possible contamination as soon as possible and to support contact tracing.

Recommendation: Explain well how these strategies are inherent intertwined and each have their own value. (Make a behaviour analysis why sharing contact information up untill now has been difficult and make adjustments.)

  • Introduce "flashing lights" (Step 6):

    • Clear recognisable and understandable symbols that render us capable to monitor our common commitment as a community (eg. green, orange, red).

    • Create transparency over the conditions where the bubbling can be loosened further or need to be tightened. Is it the percentage or the absolute number of new daily contaminations, the number of hospital admissions or another parameter? What are the thresholds for a orange or a red light? Thanks to the insight in these crucial conditions the population can monitor if the situation evolves in a favorable manner or detoriates. This will elevate the involvement and the responsability of the population and will avoid that the bubble principle is filled in to loosely. Without this insight the decisions remains a "decision ex machina" of the experts.

Recommendation: This stepped message is best communicated through an inspiring speech of policy makers.


  • Public campagn (Step 7):

    • Construct a recruting public campaing involving new terms like "bubbling", "bubblers","bubble click", etc.

    • Look for a "slogan" that expresses this common goal well (in change of the "Stay at home") and represents a social unifying goal.

    • Media can be used for this. At the moment the tone lies to one - sided on knowledge transfer, while up untill now a social unifying story - if there is any- originated rather by chance.

      • Eg. funny corona program on a public channel where social role models, but also ordinary citizens testify on how they are dealing with the bubbling, their experience with contact tracing, etc....

      • Mobilising the "wisdom of the crowd", eg creative examples of stores, companies administering the nudging priciple, creative ways to facilitate distancing, etc.

Recommendation: Use behavioural scientists as advisors or developers for such a recruting public campaign. Launch this campaign today rather then tomorrow. S


Combined approach is crucial

Through these different steps we build on diverse theoretical pillars. It's crucial the emphasize that the different steps are necessary in combination. If we limit ourselfves to just executing steps 1 till 4, then we risk not realising the benefical effect of centralising the bubble principle. It comes down to stimulating the population to a voluntary commitment within a broader strategy with attention to general behavioural rules, the rol of tracking and tracing, necessary warning indicators and a recruting public campagne. Without that necessary framework the bubble principle risks to become a "free pass" for everybody to do whatever they want.




Maarten Vansteenkiste, Karen Phalet & Omer Van den Bergh

On behalf of the national ad - hoc task force "Psychology & Corona". 30 may 2020

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