Ioannidis's 2005 paper "Why Most Published Research Findings Are False" is the most downloaded paper in the Public Library of Science and is considered foundational to the field of metascience. In the paper, Ioannidis demonstrates that most published research does not meet good scientific standards of evidence. Ioannidis has also addressed the replication crisis in diverse scientific fields including genetics, clinical trials, and neuroscience. His work has aimed to identify solutions to problems in research, and on how to perform research more optimally. Ioannidis's research at Stanford focusses on meta-analysis and meta-research – the study of studies. Thomas Trikalinos and Ioannidis coined the term Proteus phenomenon to describe tendency for early studies on a subject to find larger effect than later ones.
COVID-19
Ioannidis' commentary on the COVID-19 pandemic has been the subject of increased media attention as well as objections from other researchers since the beginning of 2020. In an editorial on STAT published March 17, 2020, Ioannidis criticized the lack of informed decision-making in the global response to the COVID-19 pandemic, calling it a "once-in-a-century evidence fiasco."
Warning to Trump
In March 2020, Ioannidis tried to organize a meeting at the White House where he and colleagues would caution President Donald Trump against "shutting down the country for very long time and jeopardizing so many lives in doing this," according to a proposal he submitted. The meeting did not come to pass, but on March 24, shortly after the proposal was sent, Trump announced that he wanted the country reopened by Easter.
Santa Clara study
Ioannidis was a co-author in the study "" released on April 17, 2020. The study asserted that the county's number of infections was 50 to 85 times higher than the official count, putting the virus’s fatality rate as low as 0.12% to 0.2%. Its conclusions were disputed by other scholars. It was reported that authors of the study received funding from JetBlue's founder, which led to criticism over a potential conflict of interest.
Press coverage
In 2010, The Atlantic wrote a lengthy piece on Ioannidis, as a part of a special edition about "Brave Thinkers". In 2014, The Economist wrote a shorter piece about the foundation, by Ioannidis and Steven Goodman, of the Meta-Research Innovation Centre at Stanford. In 2015, he was profiled in the BMJ and described as "the scourge of sloppy science".
Awards
Ioannidis has received numerous awards and honorary titles and he is a member of the US National Academy of Medicine, of the European Academy of Sciences and Arts and an Einstein Fellow. In 2019, Ioannidis was awarded the NIH's Robert S. Gordon, Jr. Lecture in Epidemiology.