Should College Algebra be a Prerequisite for Taking Psychology Statistics?

In order to consider whether a course in college algebra should be a prerequisite for taking psychology statistics, we recorded students' grades in elementary psychology statistics and in college algebra at a 4-year university. Students who earned credit in algebra prior to enrolling in statistics for the first time had a significantly higher mean statistics grade than those without algebra. However, prior credit in algebra did not significantly add to the prediction of statistics grades, after we controlled for GPA, sex, and year in college.