Departmental Factors Affecting Time-to-Degree and Completion Rates of Doctoral Students at One Land-Grant Research Institution

Time to doctoral degree has increased consistently in American universities since 1967, in some fields by as much as two years. Although time to degree varies systematically by field of study, in general, the median time spent enrolled as graduate student has increased from 6.6 years in 1983 to 7.1 in 1993. In the same period, the median time elapsed between the bachelor's degree and the doctorate rose from 9.8 to 10.5 years (Thurgood & Clarke, 1995). It is predicted that this pattern will persist, resulting in a diminished supply of highly trained workers in the future (Tuckman, Coyle, & Bae, 1990). Given the high costs associated with graduate education, the current national climate of diminishing resources for higher education, and an increased competition for these resources between undergraduate and graduate programs, understanding and examining the factors that affect students' ability to complete their degree requirements in a timely manner and considering the implications of these factors becomes crucial. Since 1960, when Berelson examined the reasons for the increase in time to degree in graduate education, several studies have been conducted to explore factors influencing this outcome. Some scholars who have investigated the influence of student characteristics on time to degree and completion rates have agreed that the potential for students to successfully complete their doctoral degrees in a relatively short time depends on a complex set of individual characteristics related to demographics, financial support and type, motivation, and ability (Abedi & Benkin, 1987; Berg & Ferber, 1983; Cook & Swanson, 1978; Gunn & Sandford, 1988; Kluever, 1995; Ott & Markewich, 1985; Tuckman, et al., 1990; Valentine, 1987; Zwick, 1991). By the same token, other scholars have studied the influence of institutional factors on student success (Bowen & Rudenstine, 1992; Dolph, 1983; Girves & Wemmerus, 1988; Golde, 1994; Jacks, Chubin, Porter, & Connolly, 1983; Lussier, 1995; Monsour & Corman, 1991; Nerad & Cerny, 1993). For the purposes of this study, student success is defined as the ability of the student to complete his/her degree requirements in a timely manner. Among the most common institutional factors analyzed in these studies are the size of the graduate program, availability and type of financial support, relationships among students and between students and faculty, kind of advising, and graduate policies and practices. Results from these studies have also indicated that the institutional factors mentioned above influenced the successful completion of graduate study in a relatively short time. Due to the validity of both approaches to studying graduate education, it can be said that personal factors alone are not sufficient to explai n or predict graduate student success. Instead, graduate education outcome seems to be better explained by the interaction between student characteristics and institutional factors. Other authors have found that time to degree and completion rate are related (Bowen & Rudenstine, 1992; Nerad & Cerny, 1993; Tuckman, 1991). These studies have found that programs with high completion rates are often those in which students take relatively short times to earn a doctoral degree. However, the literature is unclear about whether the time students spend enrolled in graduate school is a predictor of their successful completion of degree. Additional research in this direction needs to be done to confidently establish that causal relation (Tuckman, 1991). Most of the studies conducted to date have examined graduate student progress in all fields, after differentiating time to degree by field of study, concentrated only on those fields where graduate students took longer times to complete degrees (Bowen & Rudenstine, 1992; Nerad & Cerny, 1993). Furthermore, the majority of the studies on doctoral student success have been conducted by grouping departments according to disciplinary characteristics. …