2.7. Statistical Analysis
Calculations were performed using SPSS Statistics for Windows (Version 25.0, IBM Corp, Armonk, NY, USA). A significance level of 5% (two tails) was used for comparisons. In each group, the means and standard errors of the measured variables were calculated. In each experiment, the effects of the intervention on sensation scores were analysed, measuring the area under the curve normalised for baseline (except for the wanting and liking scores, which were not normalised) as follows: for each observation interval, the area was calculated as duration (min) of the observation interval × normalised score (absolute score—mean premeal score); the area under the curve during ingestion and the postprandial period (expressed as score × min) was calculated as the sum of the area of all observation intervals. In each participant, the effect of the aversive (or sham) stimulus was measured as the difference in the area under the curve on day 2 (duodenal lipids or sham infusion) minus day 1 (pre-conditioning); the effect of conditioning (previous exposure to aversive stimulus) was measured as the difference in day 3 (post-conditioning) minus day 1 (pre-conditioning). Mean values for the test group (lipid infusion) and control group (sham infusion) were calculated, and statistical analyses within groups and between groups were performed. The Shapiro–Wilk test was used to determine the normality of data distribution. Parametric normally distributed data were compared by Student’s All co-authors had access to the study data and reviewed and approved the final manuscript.