Validity and reliability of a questionnaire that aims to investigate consumption and problematic eating behaviours...

This study aimed to develop and validate a questionnaire that investigates sugar-related eating behaviour, excessive consumption, and addictive-like eating. This questionnaire was validated using a rigorous process assessing content validity, face validity, reliability testing, feasibility testing, and construct validity. Spearman's correlation coefficients and Cronbach's alpha were used to assess reliability. Feasibility testing was used to further validate and confirm the scoring/categorisation of 'low', 'medium', and 'high' scorers for use in future research. Exploratory factor analysis and reliability analysis were used to determine underlying latent factors and assess construct validity. Content validity was assessed by health professionals (n = 16), face validity was assessed by the lay public who had no expertise in nutrition or addiction (n = 20). Reliability (n = 54), repeat reliability (n = 50), and feasibility (n = 113) testing were assessed with a sample from the lay public. Spearman's correlation coefficients were in the range of 0.58-0.91 and were statistically significant (P < 0.001), indicating good temporal stability within the questionnaire. Cronbach's alpha coefficients were in the range of 0.62-0.93, indicating good internal consistency. Feasibility testing confirmed the use of calculating an 'average total score' from the data set and splitting the data set into tertiles: low, medium, and high scorers. Exploratory factor analysis confirmed three latent factors: F1: Compulsive Eating; F2: Comfort Eating; and F3: Withdrawal. Results suggest the questionnaire is highly reliable and was successfully validated. This questionnaire can be used in research to investigate problematic and addictive-like eating behaviour and its effects on ill health.