The Veg∗n Eating Motives Inventory Plus (VEMI+): A measure of health, environment, animal rights, disgust, social, pandemic and zoonotic diseases, and farm workers' rights motives.

Health, environmental concern, and animal rights are established motives for reduced meat consumption that can be measured by the Vegetarian Eating Motives Inventory (VEMI). This preregistered study aimed to expand the VEMI to include four less-studied motives: disgust, social, concern about zoonotic diseases and pandemics, and concern for workers' rights. We had three objectives: to combine the seven motives into a comprehensive model, to test if the VEMI+ scales function equivalently across omnivore and vegan groups, and to validate and differentiate these motives against external measures and meat reduction appeals. In samples of 731 omnivores and 731 vegans (total N = 1,462), we found support for the measurement invariance of a seven-factor structure across groups and created a scale with reliable measures for each dimension (ω total between 0.82 and 0.97). Vegans scored higher overall, with substantially higher scores on environmental concern, animal rights, disgust, and zoonotic disease concerns, while omnivores had slightly higher scores on health, social, and workers' rights scales. Scale scores had expected correlations with criterion measures and differentially predicted support for motive-tailored appeals. This study enhances our understanding of dietary motivations and provides a valuable tool for future research.