Whether studying physical sciences, social sciences, engineering, mathematics, humanities, or education, approximately one in every two doctoral students fail to persist to degree completion (Bowen & Rudenstine, 1992; Lovitts, 2001; Tinto, 2012). A quantitative comparative study focused on two populations; students currently enrolled in the professional doctorate EdD program and former EdD students, including students who started but did not finish the program. Research-based variables, characterized as personal and program factors driving doctoral student attrition, were tested for significance. The participation criteria defined at least 80% of the program's course content in totality was or is currently delivered online from a university offering the professional EdD degree, including affiliation with the Carnegie Project on the Education Doctorate (Allen & Seaman, 2015; Rockinson-Szapkiw et al., 2019). About half of the survey respondents attended an EdD program affiliated with the Carnegie Project on the Education Doctorate (CPED). In contrast, the other half attended an EdD program with no affiliation with CPED. The Community of Inquiry for Online Learning comprised four elements, teaching presence, social presence, cognitive presence, and emotional presence, and was the study's theoretical framework. A total of [n = 725] individuals responded to surveys, which yielded a sample size of [n = 475] usable responses from former and current EdD students. The data from 30 former students, who did not persist, was analyzed for comparative purposes. Survey respondents represented a diverse population of age, gender, ethnicity, and marital status, attending public, private, and for-profit colleges and universities from geographic locations throughout the United States. The independent variable for all but the last of 16 hypothesis tests were current and former EdD students. The dependent variables were the personal and program factors. Five hypothesis tests included the effect of a moderating or second independent variable to reveal differences between the primary independent and dependent variables. The last hypothesis test compared time-to-degree between former students who attended an EdD program affiliated with the CPED and students who attended an EdD program with no affiliation with CPED. Within the 16 statements of hypothesis were 32 sub-hypotheses tests, of which the results indicated 19 were significant. [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://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]