Certain drugs differ in their side effects depending on the gender of the patient. In a study to determine whether men or women suffer more serious side effects when taking a powerful penicillin substitute, 50 men and 50 women were given the drug. Each was asked to evaluate the level of stomach upset on a 4-point scale, where 4 = extremely upset, 3 = somewhat upset, 2 = not too upset, and 1 = not upset at all. Can we conclude that men and women experience different levels of stomach upset from the drug?