The development, psychometric properties and refinement of a food literacy scale for specific and general application

• Published in: International journal of gastronomy and food science 2024-03, Vol.35, p.100862, Article 100862
• Main Authors: Fisher, Hennie, Potgieter, Marietjie
• Format: Article
• Language: English
• Subjects: Eating behaviour; Food choices; Food literacy; Instrument validation; Middle-income; Rasch analysis
• ISSN: 1878-450X; 1878-4518
• DOI: 10.1016/j.ijgfs.2023.100862

Food literacy continues to be a developing concept, and the need for a universal definition with agreed subconstructs and validated measuring instruments continues to be a priority. The concept describes the knowledge, skills and behaviours needed to meet daily challenges in the face of growing global non-communicable diseases associated with incorrect food behaviour. This research aims to develop, refine and validate a Food Literacy Scale for context-specific and general applications. Food literacy definitions and subconstruct formulations reported elsewhere were used to guide the development of a pool of items (N = 204). This research reports on a process of refinement and validation based on a combination of CTT and Rasch modelling, using results from a middle-income database (population N = 1657, sample n = 862). The application of Rasch analysis provided credible evidence for the quality of the psychometric properties of the instrument. Pragmatic decisions were made about which items to keep or delete, based on qualitative considerations as well as comparison and contrasting of indicators derived from each statistical framework. The final instrument consisted of 95 dichotomous items grouped in six subscales, namely Procurement (11 items), Economics (9 items), Consumption (21 items), Nutrition (24 items), Food safety (17 items), and Socio-cultural aspects (13 items). The large item pool offers scope for further refinement upon implementation in different contexts. The final scale is modular, meaning that one or more subscales can be removed or replaced before implementation. Based on its excellent psychometric properties, the SAFLSTM (South African Food Literacy Scale) is suitable to measure the food literacy of middle-income consumers across many contexts.