Validation of the Dietarian Identity Questionnaire (DIQ) : A case study in Italy

An increasing number of consumers are trying to reduce and control their meat consumption and are shifting toward vegetarian, vegan, or flexitarian diets. While these diet categories are often grouped together, different psychological drivers may lead to the decision to follow a certain dietary pattern. The Dietarian Identity Questionnaire (DIQ) (Rosenfeld & Burrow, 2018) assesses how people think, feel, and behave with respect to consuming or avoiding animal products and allows us to explain the underlying psychological motivations of food choices. Considering that the psychology of eating behavior is strictly connected to the cultural context, this study (N = 678) aimed to (i) evaluate the mismatch between dietarian categorization obtained by food consumption and self-categorization; (ii) validate the Italian version of the DIQ (DIQ-I); and (iii) evaluate whether the results of the DIQ-I dimensions vary with categorization. Mismatches were evaluated using cross-tabulation and chi-square analysis, while DIQ-I was validated using confirmatory factor analysis (CFA). Finally, multiple one-way ANOVAs were conducted on groups of dieters defined by the respondents' self-categorizations and according to self-reported meat consumption. The overall findings suggest that the DIQ-I can satisfactorily depict the ideological significance of following certain diets in the Italian population. Moreover, the self-categorization results revealed that consumers' perceptions of their own diets often differ from scholars' definitions, which might imply a systematic bias in food surveys and consumers' research practices.