Box 1 Core pillars and underlying principles of crisis communication and health literate communication [9, 10, 22]

Pillar 1: preparedness

Planning & guidelines: A crisis communication plan, developed in non-crisis time, should be readily available [9]

Pillar 2: strategy

Announcing early: Accurate, comprehensive, transparent information should be shared early to build trust and facilitate behavioural change [9, 10]

Frequency: Information should be updated regularly, to reinforce earlier messages and keep the attention as a credible source [10]

Consistency: Messages across organisations should be consistent, as people inform themselves using different sources [10]

Transparency: Information should include acknowledgement of uncertainty, what is known and (still) unknown, and what actions are being undertaken to deal with the crisis, to maintain public trust and promote more deliberate decision-making [9, 10]

Pillar 3: reach

Trust: Communication with the public depends on building, maintaining and/or restoring trust as a precondition for medical advice to be believed and followed, and to ensure it truly reaches the intended audience. Trust is built through long-term relations with the public, acknowledging people’s struggles as well as, counterintuitively, scientific uncertainty [9, 10]

Accessibility (1/2): Information should be accessible through multiple channels (besides oral communication in clinical encounters) to enhance reach and impact, as a diverse audience is best reached in diverse ways [10]

Pillar 4: content of communication

Understanding the public: Crisis communication should be a dialogue, where providers communicate a message that is adapted towards the needs of their intended audience. Messages should address the concerns that live among the population [9, 10]

Actionability: Communication should include information on what the public can do themselves (for example in prevention, treatment, or coping). Materials are actionable when consumers of diverse backgrounds and varying levels of health literacy can identify what they can do based on the information presented [9, 10, 22]

Accessibility (2/2): Information should be accessible in terms of understandability and difficulty, to promote the audience’s understanding [10, 22]

Recurring theme: health literacy

Health literacy needs of the audience should be considered throughout. This specifically refers to actionability and understandability, but also considers people’s health literacy needs across all principles.For example, this includes using appropriate channels, building trust, and providing tailored guidance and support as a strategy to make sure the communication is understood and acted upon by the audience