Interactive effects refer to how different factors interact with each other to produce a combined effect that is different from the sum of their individual effects. In research, interactive effects are often studied to understand how various variables or factors influence outcomes or behavior in complex ways. This can involve examining how different genetic, environmental, or physiological factors interact to produce a specific outcome, or how interventions or treatments interact with individual characteristics to produce varying effects. Understanding interactive effects is important for developing more precise and effective interventions, treatments, or policies in various fields such as psychology, medicine, and environmental science.