When do persuasive messages on vaccine safety steer COVID-19 vaccine acceptance and recommendations? Behavioural insights from a randomised controlled experiment in Malaysia.

INTRODUCTION: Vaccine safety is a primary concern among vaccine-hesitant individuals. We examined how seven persuasive messages with different frames, all focusing on vaccine safety, influenced Malaysians to accept the COVID-19 vaccine, and recommend it to individuals with different health and age profiles; that is, healthy adults, the elderly, and people with pre-existing health conditions. METHODS: A randomised controlled experiment was conducted from 29 April to 7 June 2021, which coincided with the early phases of the national vaccination programme when vaccine uptake data were largely unavailable. 5784 Malaysians were randomly allocated into 14 experimental arms and exposed to one or two messages that promoted COVID-19 vaccination. Interventional messages were applied alone or in combination and compared against a control message. Outcome measures were assessed as intent to both take the vaccine and recommend it to healthy adults, the elderly, and people with pre-existing health conditions, before and after message exposure. Changes in intent were modelled and we estimated the average marginal effects based on changes in the predicted probability of responding with a positive intent for each of the four outcomes. RESULTS: We found that persuasive communication via several of the experimented messages improved recommendation intentions to people with pre-existing health conditions, with improvements ranging from 4 to 8 percentage points. In contrast, none of the messages neither significantly improved vaccination intentions, nor recommendations to healthy adults and the elderly. Instead, we found evidence suggestive of backfiring among certain outcomes with messages using negative attribute frames, risky choice frames, and priming descriptive norms. CONCLUSION: Message frames that briefly communicate verbatim facts and stimulate rational thinking regarding vaccine safety may be ineffective at positively influencing vaccine-hesitant individuals. Messages intended to promote recommendations of novel health interventions to people with pre-existing health conditions should incorporate safety dimensions. TRIAL REGISTRATION NUMBER: NCT05244356.

Malaysian Health Literacy: Scorecard Performance from a National Survey.

Health literacy is an indicator of a society's ability to make better health judgements for themselves and the people around them. This study investigated the prevalence of health literacy among Malaysian adults and provided an overall picture of the society's current health literacy status, which has not been previously assessed. The study also highlighted socio-demographic markers of communities with limited health literacy that may warrant future intervention. A population-based self-administered survey using the Health Literacy Survey Malaysian Questionnaire18 (HLS-M-Q18) instrument was conducted as part of the National Health Morbidity Survey 2019 in Malaysia. The nationwide survey utilized a two-staged stratified random sampling method. A sample of 9478 individuals aged 18 and above, drawn from the living quarter list, participated in the study. The health literacy score was divided into three levels; limited, sufficient, and excellent. Findings showed a majority of the Malaysian population had a sufficient health literacy level in all three domains-healthcare, diseases prevention and health promotion (49.1%, 44.2%, and 47.5%, respectively)-albeit leaning towards the lower end of the category with an average score of 35.5. The limited health literacy groups were prevalent among respondents with older age (68%), lower education level (64.8%), and lower household income (49.5%). The overall health literacy status for Malaysia was categorized at a lower sufficiency level. Future health literacy improvements should focus on communities with a limited health literacy level to improve the overall score.

Mediational effects of self-efficacy dimensions in the relationship between knowledge of dengue and dengue preventive behaviour with respect to control of dengue outbreaks: a structural equation model of a cross-sectional survey.

BACKGROUND: Dengue fever is endemic in Malaysia, with frequent major outbreaks in urban areas. The major control strategy relies on health promotional campaigns aimed at encouraging people to reduce mosquito breeding sites close to people's homes. However, such campaigns have not always been 100% effective. The concept of self-efficacy is an area of increasing research interest in understanding how health promotion can be most effective. This paper reports on a study of the impact of self-efficacy on dengue knowledge and dengue preventive behaviour. METHODS AND FINDINGS: We recruited 280 adults from 27 post-outbreak villages in the state of Terengganu, east coast of Malaysia. Measures of health promotion and educational intervention activities and types of communication during outbreak, level of dengue knowledge, level and strength of self-efficacy and dengue preventive behaviour were obtained via face-to-face interviews and questionnaires. A structural equation model was tested and fitted the data well (χ(2) = 71.659, df = 40, p = 0.002, RMSEA = 0.053, CFI = 0.973, TLI = 0.963). Mass media, local contact and direct information-giving sessions significantly predicted level of knowledge of dengue. Level and strength of self-efficacy fully mediated the relationship between knowledge of dengue and dengue preventive behaviours. Strength of self-efficacy acted as partial mediator in the relationship between knowledge of dengue and dengue preventive behaviours. CONCLUSIONS: To control and prevent dengue outbreaks by behavioural measures, health promotion and educational interventions during outbreaks should now focus on those approaches that are most likely to increase the level and strength of self-efficacy.