Validation of the Turkish Version of the Orthorexia Nervosa Inventory (ONI) in Adult Population: Its Association with Psychometric Properties

Abstract PurposeIt was aimed to examine the reliability and validity of the Orthorexia Nervosa Inventory (ONI) the Turkish version in a large adult population.MethodsIn this cross-sectional study, 710 individuals were included between the ages of 18–65 years living in Turkey. Individuals were reached via an online questionnaire (including ONI, Eating Attitudes Test-26 (EAT-26) and sociodemographic characteristics). Confirmatory factor analysis (CFA) was used to test the validity of ONI. ONI contains three sub-factors (behaviors, emotions and impairments). Analyzes were made with Lisrel 8.80 program and Statistical Package for Social Sciences 22.0 package program.ResultsThe Cronbach’s alpha coefficient was 0.906 for ONI total factor scores and Cronbach’s alpha values for “behaviours”, “impairements”, and “emotions” were found to be 0.821, 0.842, and 0.809, respectively. Confirmatory factor analysis performed supported the three-factor structure of the ONI obtained in the first sample. The CMIN / df = 5.65 and the model generally fits well to the structure (RMSEA = 0.081, CFI = 0.94, NFI = 0.91, GFI = 0.86, AGFI = 0.83). A positive and moderate relationship (r = 0.418) was found between ONI and EAT-26. A positive and low level (r = 0.160) correlation was found between ONI and body mass index. There is no statistically significant difference between ONI scores according to gender (p = 0.22).ConclusionThe findings suggest Turkish version of the ONI is a valid and reliable scale for determining the tendency for orthorexia nervosa in Turkish adult population.Level of evidenceLevel V, descriptive cross-sectional study