Abstract
AIM: To develop a structured questionnaire based on the integrated behavioural model (IBM) framework to assess social media use and dietary habits and to evaluate its validity and reliability among university students. MATERIALS AND METHODS: The study targeted undergraduate students, aged 18-25 years, from universities in Riyadh, Saudi Arabia, who actively used at least one major social media platform. The questionnaire was designed using IBM constructs, focusing on five dietary habit domains potentially influenced by social media. The questionnaire was validated through expert assessment, pilot testing, and iterative revisions to enhance clarity. The final version consists of 38 items. Internal consistency was assessed using Cronbach's alpha, and construct validity was evaluated via factor analysis, including principal component extraction and Varimax rotation. The Kaiser-Meyer-Olkin measure and Bartlett's test of sphericity were used to confirm data suitability for factor analysis. RESULTS: The study included 401 participants (mean age: 20.75 years). Social media usage was prevalent, with 51.9% of participants reporting more than 4 hours of daily use. The 38-item scale demonstrated excellent internal consistency, with Cronbach's α values between 0.953 and 0.956. Factor analysis confirmed construct validity, identifying eight factors related to dietary behaviours, including dietary habits, attitudes, and knowledge. Each domain exhibited strong factor loadings, supporting the integrity of the construct. CONCLUSION: Our theory-based questionnaire may serve as a reliable and valid tool to examine the association between social media usage and dietary behaviours in young adults. Future research should validate the instrument in more diverse populations to enhance its applicability.