The HCT Index: a typology and index of health conspiracy theories with examples of use

Background: Conspiracy theories regarding vaccination programmes, medical side effects, and cover-ups by governments or pharmaceutical companies are prevalent in many countries and have highly detrimental and far-reaching effects on people’s wellbeing. For research and policymaking in public health, it is vital to understand the nature, construction and dissemination of these health conspiracy theories (HCTs). Inspired by tale typologies developed in folkloristics, this paper presents a typology and index of international HCTs as a tool for researchers to identify and categorise the HCTs they come across, and to provide a pool of examples of HCTs which could be used in various fields of research. To illustrate this, two studies are also presented (Study 1 and Study 2).
Methods: HCTs were collected from relevant academic literature, news journalism, a survey of known health-related, general conspiracy theorist websites, and web searches based around known HCTs. From this, 14 core types were identified, and a numbered index was constructed with brief descriptions, examples, and motifs. Study 1 is a survey of HCT exposure and belief in the UK. Study 2 is a focus group discussion of health rumours in rural Sri Lanka including discussion of HCTs.
Results: The HCT Index provides valuable insights into the international dissemination of HCTs. Study 1 found that familiarity with and belief in HCTs were high: 97% of Britons are familiar with at least one HCT and 49% of Britons believed that at least one HCT was likely to be true. Study 2 highlighted concerns over threats to fertility and about how to verify information that falls outside of typical experience.
Conclusions: The HCT Index provides a useful framework for future cross-cultural research. As a typology it encompasses a wide range of beliefs which can be more effectively categorized and compared and, ultimately, challenged.