2.6. Statistical Analysis
PVT
The statistical analyses were computed using Jamovi (version 1.6.15, 2022). Values were expressed as the mean ± SEM. Values for the PVT RT, KSS, IAF, and EEG band power were analyzed using a linear mixed model including fixed effects for awakening duration (repeated measures ranging from 2 to 32 h), acute treatment (caffeine or placebo, repeated measure), and habitual caffeine consumption (non-repeated measure).Secondly, post hoc analyses were performed to compare the differences between the caffeine consumption groups. Differences in the subjects’ characteristics between the groups of habitual caffeine consumption were evaluated using a one-way ANOVA (3 levels). The significance level was set at Repeated measures correlations were computed between KSS, daily caffeine consumption levels, RT, and IAF. All post hoc analyses were performed using Student’s 