2.6. Data Analysis
satiety, sensory loss status substituting
Study data were double data entered into REDCap (Electronic Data Capture), a secure internal computerized database system [Participants’ demographic characteristics, self-reported sensory change since 35 years old and responses to the VARSEEK questionnaire were tabulated using summary statistics. All participants attended both sittings for each meal type so there were no missing data for the study.Differences in protein and energy intakes, food liking, flavor intensity and satiety between test meal conditions (i.e., S or NS) were analyzed using a linear mixed effects model (LMM) with a random subject effect (Model 1). The LMM model consisted of the treatment sequence group (i.e., S->NS or NS->S), test meal period (i.e., visit 1 or visit 2), and test meal condition (i.e., S or NS) as fixed effects. Differences in the effect of spice addition between protein sources (M or V) was tested using a second model. In Model 2, we analyzed data from both entrée types together by introducing protein source (i.e., M or V protein) and its interaction term with test meal condition (i.e., S or NS) into Model 1 while allowing protein source to have different random subject effects. Under Model 2, the protein source effect was assessed by testing the interaction terms of protein source and meal condition. Separate exploratory analyses of any moderation effects of change in self-reported sensory acuity or food-variety-seeking tendency were conducted for the two protein sources. To investigate whether the spices’ effect was stronger in participants with vs. without decreased sensory acuity, we analyzed the data in the same fashion as Model 2 with sensory loss status substituting for protein source.Other analyses: Individual scores for the difference between meal conditions in protein consumption were correlated with changes in liking scores, flavor intensity ratings, and hunger and satiety scores, respectively. In addition, the amount food consumed was correlated with the VARSEEK questionnaire composite score to assess any effect of food-variety-seeking behavior on intake. Finally, whether or not the participant had experienced COVID-19 (more than 6 months prior to testing) was correlated with protein intake. The appropriateness of normality assumptions was assessed by examining residual plots from the mixed model.