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

Abstract

Purpose To examine the reliability and validity of the Turkish version of the Orthorexia Nervosa Inventory (ONI) in a large adult population. Methods Included in this cross-sectional study, were 710 individuals living in Turkey who were between 18 and 65 years of age. The individuals were reached via an online questionnaire that included their sociodemographic characteristics and the ONI and Eating Attitude Test-26 (EAT-26). Confirmatory factor analysis (CFA) was used to test the validity of the ONI. The ONI contains three sub-factors (behaviors, emotions, and impairments). Analyses were conducted using LISREL 8.80 for Windows and IBM SPSS Statistics for Windows 22.0. Results The Cronbach's alpha coefficient was 0.91 for the ONI total factor scores and Cronbach alpha values for behaviors, impairments, and emotions were found to be 0.82, 0.84, and 0.81, respectively. The CFA performed supported the three-factor structure of the ONI obtained in the first sample. The minimum discrepancy per degree of freedom = 5.65 and the model generally fit well to the structure (RMSEA = 0.08, CFI = 0.94, NFI = 0.93, SRMR = 0.07, IFI = 0.94). A positive and moderate relationship (r = 0.42) was found between the ONI and EAT-26. A positive and low level (r = 0.16) correlation was found between the ONI and body mass index. There was no statistically significant difference between the ONI scores according to gender (p = 0.22). Conclusion The findings suggested that the Turkish version of the ONI is a valid and reliable scale for determining the tendency for ON in a Turkish adult population.