ANOVA should be used when: 1. You have multiple groups to compare. For instance, comparing the efficacy of different nanoparticles in drug delivery. 2. You want to study the effect of one or more independent variables on a dependent variable, such as the impact of temperature and pressure on the size of synthesized nanoparticles. 3. Ensuring that the assumptions of ANOVA (normality, homogeneity of variances, and independence) are met.