Investigating the structure of ORTO-15: a meta-analytical simulation study

Area of Science:

• Psychiatry
• Psychology
• Eating Disorders

Background:

• Orthorexia Nervosa (ON) is a proposed eating disorder characterized by an unhealthy obsession with healthy eating.
• Existing measures for ON, such as the ORTO-15, have faced criticism regarding their validity and reliability.
• There is a recognized need for validated tools to accurately assess ON prevalence and characteristics.

Purpose of the Study:

• To re-evaluate the psychometric properties of the ORTO-15 measure for assessing Orthorexia Nervosa.
• To develop a concise and validated version of the ORTO-15 for ON assessment.
• To demonstrate the utility of existing data in advancing ON research.

Main Methods:

• A review of psychometric studies on the ORTO-15 structure was conducted.
• Six consistently present items across studies were selected for analysis.
• Effect sizes of factor loadings were estimated and used in Monte Carlo simulations (N=100, 500, 1000) to test model validity.

Main Results:

• The six-item version of the ORTO-15 demonstrated validity and reliability in assessing ON.
• Monte Carlo simulations confirmed the structural validity of the proposed six-item model.
• The findings support the continued use and refinement of existing measures in ON research.

Conclusions:

• A six-item version of the ORTO-15 is a psychometrically sound instrument for measuring Orthorexia Nervosa.
• This validated scale offers a valuable tool for future ON research and clinical assessment.
• The study advocates for building upon existing data to enhance understanding and research of ON.