• The values of the dependent variable show a normal distribution.
• The data shows homogeneity of variance. It means that the data in each group being compared show similar variations. In the case of different variances, the ANOVA is not applicable to the data.
• An additional assumption is that the data must be collected through a statistically valid method. But if the data fails to comply with this assumption, and you need to control data, you can use ANOVA with blocking variables. A blocking variable is a variable that affects the experimental outcome, but itself is not of primary interest to the experimenter. These are included in the experiments to reduce the effect of nuisance factors.