Your rating variable is ordinal, so do not use anova. Also, since each participant have rated 30 statements, you should not assume independence. Maybe try ordinal regression with Participant as a random effect.

A similar problem is discussed at What regression model to use for judgment data?, also How to use ordinal logistic regression with random effects?

Your rating variable is ordinal, so do not use anova. Also, since each participant has rated 30 statements, you should not assume independence. Maybe try ordinal regression with Participant as a random effect.

A similar problem is discussed at What regression model to use for judgment data?, also How to use ordinal logistic regression with random effects?