Tortured confessions? Potentially erroneous statistical inferences may underpin misleading claims of harms in reanalyses of COVID-19 and HPV vaccines.

The safety and efficacy of vaccination is a subject contentious in the public mind. Despite overwhelming evidence of their benefits to public health, COVID-19 and human papilloma virus (HPV) vaccines have been the focus of intense concerns. While the original phase III trials and post-market phase IV studies have continued to show their benefits and positive safety profile, some authors have attempted to reassess the original trial data, purporting to showing hidden harms for both COVID-19 and HPV vaccines. It is critical to ascertain why such divergent claims could stem from analysis of the same data, and this work accordingly examines these reports. In both cases, we find that erroneous statistical assumptions and unwarranted inferences are likely to have influenced the conclusions drawn, and identifies choices that would tend to result in spurious findings. This work also examines the wider issues with unregistered posthoc examinations on known trial data without preregistration, and how this may result in data-dredging, the torturing of data until it confesses to non-existent relationships, and how we might prevent against this on vaccine science.