Vol.:(0123456789) 1 3 Eating and Weight Disorders - Studies on Anorexia, Bulimia and Obesity (2021) 26:345–366 https://doi.org/10.1007/s40519-020-00858-y ORIGINAL ARTICLE Structural validity, measurement invariance, reliability and diagnostic accuracy of the Italian version of the Yale Food Addiction Scale 2.0 in patients with severe obesity and the general population Gian Mauro Manzoni 1,2  · Alessandro Rossi 3,4  · Giada Pietrabissa 1,5  · Stefania Mannarini 3,4  · Mariantonietta Fabbricatore 6  · Claudio Imperatori 6  · Marco Innamorati 6  · Ashley N. Gearhardt 7  · Gianluca Castelnuovo 1,5 Received: 29 October 2019 / Accepted: 24 January 2020 / Published online: 6 February 2020 © Springer Nature Switzerland AG 2020 Abstract Purpose To examine the structural validity, measurement invariance, reliability, and some other psychometrical properties of the Italian version of the Yale Food Addiction Scale 2 (I-YFAS 2.0) in patients with severe obesity and the general population. Methods 704 participants—400 inpatients with severe obesity and 304 participants enrolled from the general population— completed the I-YFAS 2.0 and questionnaires measuring eating disorder symptoms. A frst confrmatory factor analysis (CFA) tested a hierarchical structure in which each item of the I-YFAS 2.0 loaded onto one of the twelve latent symptoms/ criteria which loaded onto a general dimension of Food Addiction (FA). The second CFA tested a frst-order structure in which symptoms/criteria of FA simply loaded onto a latent dimension. Measurement invariance (MI) between the group of inpatients with severe obesity and the sample from the general population was also tested. Finally, convergent validity, test–retest reliability, internal consistency, and prevalence analyses were performed. Results CFAs confrmed the structure for the I-YFAS 2.0 for both the hierarchical structure and the frst-order structure. Confgural MI and strong MI were reached for hierarchical and the frst-order structure, respectively. Internal consisten- cies were shown to be acceptable. Prevalence of FA was 24% in the group of inpatients with severe obesity and 3.6% in the sample from the general population. Conclusions The I-YFAS 2.0 represents a valid and reliable questionnaire for the assessment of FA in both Italian adult inpatients with severe obesity and the general population, and is a psychometrically sound tool for clinical as well as research purposes. Level of evidence Level V, descriptive study. Keywords Food addiction · Obesity · YFAS · Scale validation · Psychometric properties · Measurement invariance Introduction In the last 10 years, the construct of food addiction (FA) has become more and more popular [1–4], and has received increasing interest in both clinical and research practice [2, 5]. One of the reasons for its popularity could be attributed to its dual nature [2–4], that led to two hypotheses: Some individuals could be addicted to food and/or to their eating behavior [6]. Indeed, the construct of FA refers to the idea that high calories (and/or highly processed foods) should activate an addiction-like response in individuals [7] that may lead to excessive food consumption [8]. Therefore, FA seems to share clinical characteristics of some eating dis- orders (EDs, e.g., bulimia nervosa, binge eating disorder) Gian Mauro Manzoni and Alessandro Rossi equally contributed to this work. Electronic supplementary material The online version of this article (https://doi.org/10.1007/s40519-020-00858-y) contains supplementary material, which is available to authorized users. * Alessandro Rossi alessandro.rossi.27@phd.unipd.it Extended author information available on the last page of the article