This study has provided insights into the factors that influence doctoral student quantitative course success but also increased the lens for further research. The current study explored the relationship between master's degree type, years since completing a master's degree, self-efficacy scores and cumulative GPA in Research I, Research II, and Applied Statistics in Trevecca's online Ed.D. program. The correlation analyses conducted found no discernible relationship between the years since completing a master's degree or the type of master's degree held by Trevecca's online EdD students and their cumulative GPA in quantitative courses. However, the one-way ANOVA test conducted showed that self-efficacy in math competency has a weak positive correlation with the cumulative GPA in quantitative courses. The implications of this study offer Trevecca and other institutions a bridge between theory and practice, enabling them to build better strategies, guide more students through their academic programs, and create a roadmap for future research endeavors with actionable insights. To conduct the research effectively, it is recommended to collect students' cumulative GPA immediately after each quantitative course and obtaining self-efficacy in math scores from students before their first quantitative course to capture their initial confidence levels, mitigating potential influences by their actual performance in subsequent courses. Future researchers may uncover better practicability by combining another area of Tinto's model to understand how the student attributes and student experience relate to quantitative course success. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]