Does the messenger make the difference? Perceived reliability of health information sources during the COVID-19 pandemic in multi-ethnic Malaysia.

The COVID-19 infodemic highlighted the need to identify the extent to which health information messengers were perceived as reliable by the public in supporting effective public health communication. A question that remains is whether there are differences across ethnic groups in information processing. This study examines the perceived reliability of three formal sources (healthcare workers, scientists, and non-governmental organisations [NGOs]) and four informal sources (religious leaders, community leaders, interpersonal sources, and influencers) among Malaysia's multi-ethnic population through a cross-sectional online survey conducted between April and June 2021. Logistic regression was used to identify the perceived reliability of different information sources in steering vaccination intentions. We further examine the extent to which there were ethnic differences in the perceived reliability of these sources across education levels and age groups. Adjusted predicted probabilities were estimated to illustrate these differences. Among 5,784 participants, formal sources were consistently perceived as the most reliable across all ethnic groups and, together with community leaders, were identified as the main information sources influencing vaccination intention. We find large predicted probabilities of perceiving healthcare workers and scientists as reliable across most groups (≥ 80%), except among Indigenous groups who exhibit lower education attainment and are older (≤ 78%). Across education levels and age groups, Indians and Chinese exhibit higher predicted probabilities of perceiving NGOs as reliable, averaging approximately 80% and 75%, respectively, compared with approximately 65-70% among Malays and Indigenous groups. In contrast, predicted probabilities of perceiving community leaders as reliable were moderate across all ethnicities at the lowest education level and youngest age group (45 - 55%). This pattern remained relatively stable across higher education levels and age groups among Malays and Indigenous groups, but generally decreased among Chinese and Indian respondents. These results suggest that healthcare workers and scientists ought to remain central to health communication strategies, while NGOs and community leaders may play complementary roles. Multi-messenger approaches may enhance the effectiveness of public health responses during health crises.