You have been asked to evaluate the effects of a new educational video that was developed to reduce racial prejudice among adolescents. You plan to administer a pretest measure of racial attitudes to 60 adolescent participants, then randomly assign these participants to watch either the anti-prejudice video, an educational video about volcanoes, or no video.

Afterwards, the participants will complete the measure of racial attitudes a second time.

However, you are concerned that the first administration of the attitudes measure may create pretest sensitization, thereby directly affecting participants attitudes. Explain how you could redesign the experiment to see whether pretest sensitization occurred.

(Hint: You will probably use a 3 x 2 factorial design.) What pattern of results would suggest that pretest sensitization had occurred?