The documentary An Inconvenient Study, produced by Del Bigtree and the Informed Consent Action Network (ICAN), centers on an unpublished retrospective birth cohort study conducted by researchers at Henry Ford Health System, led by Dr. Marcus Zervos, head of infectious diseases. Completed around 2020, the study compared health outcomes in vaccinated and unvaccinated children using existing medical records from the institution, which had previously run Moderna COVID-19 vaccine trials and maintained a pro-vaccine stance.

Bigtree recounts initiating contact with Dr. Zervos during a 2016 dinner while touring for his earlier film Vaxxed. He challenged Zervos to perform a vaccinated-versus-unvaccinated comparison of all health outcomes, arguing that true scientific integrity required testing such claims from a pro-vaccine perspective to minimize perceived bias from critics. After years of follow-up, Zervos and his team completed the analysis but declined to publish or submit it for peer review. Bigtree alleges this stemmed from fear of career repercussions in a climate hostile to findings questioning vaccine safety.