Open Peer Review on Qeios External validation of biomarkers of fatty liver in the general population: the Bagnacavallo study Francesco Giuseppe Foschi 1 , Fabio Conti 1 , Marco Domenicali 2 , Pierluigi Giacomoni 1 , Alberto Borghi 2 , Vittoria Bevilacqua 1 , Lucia Napoli 1 , Dante Berardinelli 1 , Mattia Altini 1 , Alessandro Cucchetti 2 , Giorgio Ercolani 2 , Andrea Casadei- Gardini 3 , Stefano Bellentani 4 , Amalia Gastaldelli 5 , Claudio Tiribelli 4 , Giorgio Bedogni 4 1 Azienda Unità Sanitaria Locale della Romagna 2 University of Bologna 3 Università degli Studi di Modena e Reggio Emilia 4 Italian Liver Foundation 5 Italian National Research Council Funding: The present analysis was sponsored by a research grant from Gilead (Milan, Italy) to the Italian Liver Foundation. The Sponsor had no role in the design and conduct of the study; in the collection, analysis, and interpretation of the data; or in the preparation and review of the manuscript. Potential competing interests: Giorgio BEDOGNI is a co-founder of Qeios. Abstract Objective: We externally validated the fatty liver index (FLI), the lipid accumulation product (LAP), the hepatic steatosis index (HSI), and the Zhejiang University index (ZJU) for the diagnosis of fatty liver (FL) and non-alcoholic fatty liver disease (NAFLD) in the general population. Subjects and Methods: The validation was performed on 2159 citizens of the town of Bagnacavallo (Ravenna, Italy). Calibration was evaluated by calculating the calibration slope and intercept and by inspecting calibration plots; discrimination was evaluated using the c-statistic. Results: The average calibration slope was 1 and the average intercept was 0 for all combinations of outcomes and Qeios, CC-BY 4.0 · Article, November 24, 2020 Qeios ID: CD6LGJ · https://doi.org/10.32388/CD6LGJ 1/16