Statistical analysis
Linear mixed-effects models in a 2 (condition) × 4 (time) design were used to assess the outcome variables; the models included product sequence (covariate), condition, time, and time-by- condition as fixed factors and subject ID as a random intercept, which allows the model intercept to vary based on the subject. Given the within-subject study design and the non-independent nature of the values of each outcome variable, the application of such linear mixed-effects models and the inclusion of a by-subject random intercept is appropriate [