According to Harpe (2015), aggregated rating scale data such as the data we collected can be treated as continuous data; he further advocates that more advanced statistical models would be more powerful than a simple group comparison via t-tests or analysis of variance tests (ANOVA).
a linear relationship was assumed, and linear mixedeffects modelling was applied in our analyses with the 'lme4' package (Bates et al., 2015) in R (R Core Team, 2018).