Initial external validation of REGRESS in public health graduate students.

Linear regression is typically taught as a second and potentially last required (bio)statistics course for Public Health and Clinical and Translational Science students. There has been much research on the attitudes of students toward basic biostatistics, but there has not been much assessing students' understanding of critical regression topics. The REGRESS (REsearch on Global Regression Expectations in StatisticS) quiz developed at Mayo Clinic utilizes 27 questions to assess understanding for simple and multiple linear regression. We performed an initial external validation of this tool with 117 University of Michigan public health students. We compare the results of pre- and postcourse quiz scores from the Michigan cohort to scores of Mayo medical students and professional statisticians. University of Michigan students performed higher than Mayo students on the precourse quiz due to previous related coursework, but did not perform as high postcourse indicating the need for course modification. In the Michigan cohort, REGRESS scores improved by a mean (standard deviation) of 4.6 (3.4), p < 0.0001. Our results support the use of the REGRESS quiz as a learning tool for students and an evaluation tool to identify topics for curricular improvement for teachers, while we highlight future directions of research.