Interpretation of the main effects must be made taking into consideration any 1)interaction 2)controlled variables 3)initial differences 4)randomized designs. answer and explain. Solution Answer : Interaction A statistical interaction occurs when the effect of one INDEPENDENT variable on theDEPENDENT variable changes depending on the level of another independent variable. Like the IQ of a 15yr old girl is different from the IQ level of 80 yr old woman.