Validity and reliability of Food–Mood Questionnaire (FMQ)

Background: The need for short and validated questionnaires to evaluate dietary patterns (DPs) and mental distress in clinical and research settings is increasing. Aim: The purpose of this study was to develop and validate a Food–Mood Questionnaire (FMQ) to assess DPs in relation to mental distress. Method: A standard validation protocol that included item development, pilot–testing, test–retesting, and a series of statistical validation analyses was used. Content, face, internal, construct and external validity as well as reliability were confirmed. Content and face validity were evaluated qualitatively. Results: Principal component analysis (PCA) for construct validity generated five sub-scales which reflected internal consistency (Cronbach’s α > 0.70) and internal reliability (intraclass correlation coefficient ranged between 0.619 and 0.884; p < 0.01; confidence interval 95%). External validity was also confirmed. A total of 563 participants from four different continents completed the survey online. PCA generated five different subscales. Mental distress was associated with regular consumption of fast-food, a DP known to induce anxiety and depression. Conclusion: The FMQ is a validated and a reliable tool with many potential applications that could be used with prophylactic and therapeutic approaches.