Background/Objectives: A vegan diet excludes all animal products and may lead to nutrient deficiencies if not properly balanced. The VEGANScreener (VS) questionnaire was developed to evaluate and monitor the diet quality of vegans in Europe. We aimed to evaluate the construct validity and internal consistency reliability of the VS.

Methods: The total VS comprises 29 food groups (score 0-66). Two sub-metrics are the VS+ (17 healthy items, ranging from 0-42) and the VS- (12 unhealthy items, ranging from 0-24), which focus on the frequency of consumption of key food groups/nutrients among vegans. A higher score for all three metrics indicates a healthier diet. Participants were stratified into tertiles based on their VS scores. For the VS-, higher scores indicate lower consumption of unhealthy foods. Internal consistency of the VS scores was evaluated using Cronbach’s alpha, with 95% confidence intervals (CIs) obtained by a bootstrap procedure. Predictive validity was assessed using multiple regression analyses between VS scores, health outcomes, and lifestyle scores.

Results: A total of 397 vegans (57% female) were included in the analysis. The mean (standard deviation) age was 36 (± 10.1), with a mean of 6 (± 4.8) years of vegan diet duration. Participants in the highest tertile (T3) of the total VS were older, married, and less likely to be smokers compared to the lowest tertile (T1). The Cronbach α (95%CI) was 0.78 (0.74- 0.80) for the total VS, 0.72 (0.69- 0.76) for the VS+, and 0.75 (0.71- 0.79) for the VS-. Higher adherence (T3) to the total VS was significantly associated with reduced waist circumference (βT3 = -1.26, 95%CI; -2.43, -0.08; p-trend = 0.035) and increased lifestyle score (βT3 = 0.46, 95%CI; 0.20, 0.73; p-trend = 0.001) compared to the lowest adherence (T1). Participants with a lowest consumption of unhealthy foods (as indicated by higher VS- values) were significantly inversely associated with BMI (βT3 = -1.14, 95%CI; -1.81, -0.46; p-trend = 0.001), waist circumference (βT3 = -1.92, 95%CI; -3.17, -0.67 p-trend = 0.005) and increased lifestyle score (βT3 = 0.56, 95%CI; 0.27, 0.84; p-trend ≤ 0.001).

Conclusions/Recommendations: The VS scores showed good validity and internal consistency. The VS questionnaire could be a useful instrument to evaluate the diet quality in vegans.

Funding: ERA-Net HDHL-INTIMIC (No. 727565); Spanish Ministry of Science, Innovation and Universities within the framework of Plan de recuperación, transformación y resiliencia-Next Generation EU (No. AC21_2/00015).