Why a study claiming vaccines cause chronic illness is severely flawed – a biostatistician explains the biases and unsupported conclusions
- Written by Jeffrey Morris, Professor of Public Health and Preventive Medicine, University of Pennsylvania
Biases in designing a study can weaken how well the evidence supports the conclusion.FatCamera/E+ via Getty ImagesAt a Senate hearing on Sept. 9, 2025, on the corruption of science, witnesses presented an unpublished study that made a big assertion.
They claimed that the study, soon to be featured in a highly publicized film called “An...