Personalization has often been described as the gold standard of training, but the research establishing a basis for personalization is limited. In this paper, we report results from comparing six factors that appear in current theories about personalization: generation; education; exposure to technology; knowledge pre-test; skill pre-test; and skill testing during training. Participants in this study were randomly assigned to two groups, allowing us to evaluate the hypothesis that younger, more technically sophisticated students will benefit more from active, technology-based training. One group studied traditional multimedia instruction (IMI) that explained the tasks; the second group received hands-on practice from an intelligent tutoring system (ITS). Results from analysis of covariance indicated that differences in age, education, exposure to technology, initial knowledge, and initial skill were not strongly related to final performance, when training treatments were taken into account. Skill testing during training proved somewhat more consistently related. None of the treatment by covariate interactions, however, yielded a statistically significant effect, so there was no support for changing instructional methods based on any of the factors studied. Instead, the hands-on practice provided by the ITS had a consistent, positive effect. The practical implications for personalized training are discussed.