Abstract
BACKGROUND: Unlike eating disorders (ED) that are officially recognized and focusing on the quantity of food, Orthorexia Nervosa (ON) revolves around an unhealthy fixation on the quality of food eaten. Existing ON scales differ in how these conceptualize and define ON, ensuing inconsistency in assessments that not only affects the validity and reliability of ON related research, but also impacts the ability of healthcare professionals to identify and provide support for individuals struggling with ON. OBJECTIVE: Create the first Eastern locally validated tool that considers the cultural nuances and specificity of the Lebanese general population's eating attitudes and their social context, addresses the limitations of existing scales and thereby provides a valid instrument that can be used in Lebanon and culturally-similar countries. METHODS: Data were collected between September 2023 and February 2024, enrolling 320 participants for the exploratory factor analysis and 658 for the confirmatory analysis. RESULTS: Starting from an initial pool of 25 items, the exploratory-confirmatory (EFA-CFA) factor analyses retained 13 items. The LONI showed a unidimensional factor structure, and satisfactory convergent and concurrent validity with a composite reliability (ω and α) of 0.90 providing clear evidence of its high reliability, supporting the stability and consistency of LONI scores across different subsamples. The structural characteristics, factor loadings, and item intercepts of the LONI remained consistent regardless of gender, affirming the tool's stability and reliability in measuring ON traits across diverse populations. CONCLUSION: The LONI is a valid tool for assessing ON, particularly in accounting for Lebanese and culturally similar populations. The scale's unidimensional structure allows for straightforward calculation of the score, making it practical for both clinical and research applications, while offering a unique advantage in considering regional dietary patterns compared with existing ON screening tools due to its cultural specificity and psychometric strengths. The ON prevalence was high in the present sample, underscoring the significance of sociocultural and behavioral factors in its manifestation.