BACKGROUND
The propagation of health misinformation through social media has become a major public health concern over the last two decades. Although today there is broad agreement among researchers, health professionals, and policy makers on the need to control and combat health misinformation, the magnitude of this problem is still unknown. Consequently, before adopting the necessary measures for the adequate control of health misinformation in social media, it is fundamental to discover both the most prevalent health topics and the social media platforms from which these topics are initially framed and subsequently disseminated.
OBJECTIVE
This systematic review aims to identify the main health misinformation topics and their prevalence on different social media platforms, focusing on methodological quality and the diverse solutions that are being implemented to address this public health concern.
METHODS
This systematic review was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines (PRISMA). We searched PubMed, MEDLINE, Scopus and the Web of Science for articles published in English before March 2019 with a particular focus on studying health misinformation in social media. We defined health misinformation as a health-related claim based on anecdotal evidence, false, or misleading due to the lack of existing scientific knowledge. The criteria for inclusion were: 1) articles that focused on health misinformation in social media, including those in which the authors discussed the consequences or purposes of health misinformation; and 2) studies that described empirical findings regarding the measurement of health misinformation in these platforms.
RESULTS
A total of 69 studies were identified as eligible, covering a wide range of health topics and social media platforms. The topics were articulated around six principal categories: vaccines (32%), drugs or smoking (22%), non-communicable disease (19%), pandemics (10%), eating disorders (9%), and medical treatments (7%). Studies were mainly based on five methodological approaches: Social Network Analysis (28%), Evaluating Content (26%), Evaluating Quality (24%), Content/Text analysis (16%) and Sentiment Analysis (6%). Health misinformation proved to be the most more prevalent in studies related to smoking products and drugs such as opioids or marijuana. Posts with misinformation reached 87% in some studies focused in smoking products. Health misinformation about vaccines was also very common (43%), but studies reported different levels of misinformation depending on the different vaccines, with the Human Papilloma Virus (HPV) vaccine being the most affected. Secondly, health misinformation related to diets or pro eating disorders (pro-ED) arguments were moderate in comparison to the aforementioned topics (36%). Studies focused on diseases (i.e. non-communicable diseases and pandemics) also reported moderate misinformation rates (40%), especially in the case of cancer. Finally, the lowest levels of health misinformation were related to medical treatments (30%).
CONCLUSIONS
Prevalence of health misinformation was most common on Twitter and on issues related to smoking products and drugs. However, misinformation is also high on major public health issues such as vaccines and diseases. Our study offers a comprehensive characterization of the dominant health misinformation topics and a comprehensive description of their prevalence in different social media platforms, which can guide future studies and help in the development of evidence-based digital policy actions plans.
CLINICALTRIAL
Prevalence of health misinformation in social media: a systematic review (Preprint)
