In May 2019 King’s College London conducted an enquiry into publications authored by Professor Hans Eysenck with Professor Ronald Grossarth Maticek. The enquiry considered all the articles in peer reviewed journals where the two authors appeared together and analysed data relevant to personality and physical health outcomes. The enquiry concluded that: “…we consider the published results of studies that included the results of the analyses of data collected as part of the intervention or observational studies to be unsafe…” Follow-up investigation: Subsequent to this investigation, further concerns have been raised by Professor Anthony Pelosi (Visiting Consultant Psychiatrist, Priory Hospital, Glasgow) with regards to publications that analysed data relevant to personality and physical health outcomes which are sole authored by Professor Eysenck. King’s College London have considered these concerns and because the number of potentially relevant publications is high and far reaching, including journal articles and books, we cannot with certainty locate and review all relevant sources which are of potential concern. However, based on enquiries to date we can confirm that any publication which relies on the data from those co-authored publications which King’s has already deemed to be unsafe, should also be considered unsafe. This statement relates to only this specific body of research covered by the 2019 Enquiry. Future action: Any journal or publisher which hosts any publications either sole authored by Professor Hans Eysenck or co-authored by Professor Hans Eysenck with Professor Ronald Grossarth Maticek which rely on data from any of the papers listed in the 2019 Enquiry, is advised to provide a link to this public statement to alert those accessing to these concerns. King’s College London now considers its investigations into this matter concluded. Published 01 April 2023: In response to an open letter to Professor Edward Byrne, President and Principal of King’s College London, from David F Marks, Editor of the Journal of Health Psychology, and subsequent publication in the Journal of Health Psychology*, King’s convened a committee with an independent chair, to examine research papers authored by Professor Hans Eysenck with Professor Ronald Grossarth-Maticek which named the Institute of Psychiatry as an institutional affiliation. The open letter stated that the publications of ‘immediate concern’ were those jointly authored by Eysenck and Grossarth-Maticek. These formed the baseline data and were the remit of the enquiry committee. The committee found the results of the papers to be unsafe, and King’s wrote to the editors of the journals concerned recommending retraction.

*’Personality and fatal diseases: Revisiting a scientific scandal’, Pelosi, Journal of Health Psychology, 2019, DOI:10.1177/1359105318822045