Using health literacy principles to improve understanding of evolving evidence in health emergencies: Optimisation and evaluation of a COVID-19 vaccination risk-benefit calculator

Carissa Bonner; Melody Taba; Michael Anthony Fajardo; Carys Batcup; Ben R Newell; Amy X Li; Helen J Mayfield; Colleen L Lau; John C B Litt

doi:10.1016/j.vaccine.2024.126296

Using health literacy principles to improve understanding of evolving evidence in health emergencies: Optimisation and evaluation of a COVID-19 vaccination risk-benefit calculator

Vaccine. 2024 Oct 24;42(24):126296. doi: 10.1016/j.vaccine.2024.126296. Epub 2024 Sep 3.

Authors

Carissa Bonner¹, Melody Taba², Michael Anthony Fajardo², Carys Batcup², Ben R Newell³, Amy X Li⁴, Helen J Mayfield⁵, Colleen L Lau⁵, John C B Litt⁶

Affiliations

¹ Sydney Health Literacy Lab, School of Public Health, Faculty of Medicine & Health, University of Sydney, NSW, Australia; Menzies Centre for Health Policy and Economics, Faculty of Medicine & Health, University of Sydney, NSW, Australia. Electronic address: carissa.bonner@sydney.edu.au.
² Sydney Health Literacy Lab, School of Public Health, Faculty of Medicine & Health, University of Sydney, NSW, Australia.
³ School of Psychology, Faculty of Science, UNSW, Sydney, Australia; Institute for Climate Risk and Response, UNSW, Sydney, Australia.
⁴ School of Psychology, Faculty of Science, UNSW, Sydney, Australia; Department of Experimental Psychology, University of Oxford, Oxford, UK.
⁵ Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Australia.
⁶ College of Medicine and Public Health, Finders University, Australia.

PMID: 39232400
DOI: 10.1016/j.vaccine.2024.126296

Abstract

Background: Risk communication tools based on epidemiological models can help inform decision-making, but must be responsive to health literacy needs to be effective. To facilitate informed choice about risks and benefits of COVID-19 vaccination, an epidemiological model called the COVID-19 Risk Calculator (CoRiCal) tool was developed by a multi-disciplinary team.

Aim: This paper demonstrates how to use health literacy principles to improve consumer understanding of COVID-19 and vaccine effects, using a range of methods that could be applied to any health emergency.

Methods: Stage 1: Health literacy optimisation and user testing to reduce improve understandability (n = 19). Stage 2: Experiments to explore the effect of risk communication formats on perceived understanding including probability, graphs, evaluative labels and comparison risks (n = 207). Stage 3: Randomised controlled trial (n = 2005) with 4 arms: 1) standard government information; 2) standard CoRiCal output based on bar graphs; 3) animation explaining bar graphs in "x per million" format; 4) animation explaining bar graphs in "1 in x chance" format. The primary outcome was knowledge about COVID-19 risk.

Results: Stage 1 reduced the complexity of the text and graphs. Stage 2 showed that different risk communication formats change perceived understanding, with a preference for evaluative labels across 2 experiments and some indication people with lower health literacy had a greater preference for bar graphs. Stage 3 showed both animations increased knowledge compared to standard government information. There was no difference between the probability formats, or by health literacy level.

Discussion: The results showed that simple explanations of complex epidemiological models improve knowledge about COVID-19 and vaccination. This demonstrates how health literacy design principles and short animations can be used to support informed decision making about health emergencies.

Keywords: COVID-19; Health literacy; Risk communication; Vaccination.

Publication types

Randomized Controlled Trial

MeSH terms

Adolescent
Adult
Aged
COVID-19 Vaccines* / administration & dosage
COVID-19* / epidemiology
COVID-19* / prevention & control
Comprehension
Decision Making
Emergencies
Female
Health Communication / methods
Health Knowledge, Attitudes, Practice*
Health Literacy*
Humans
Male
Middle Aged
Risk Assessment
SARS-CoV-2*
Vaccination* / psychology
Young Adult

Substances

COVID-19 Vaccines