| Doctoral students are taking longer to complete their degrees than at any time since Ph.D. duration records have been maintained. The median registered time-to-degree for students in all disciplines increased from 5.0 to 7.2 years in 1967 to 1996. Although the magnitude of the increase varies considerably by discipline type, time-to-degree has increased in all fields with the largest increases in the humanities, social sciences, and education. While a few previous studies have explored doctoral time-to-degree from the student factor, this study focuses on the factors leading one department in a discipline to produce doctorates faster than others in the same discipline.;Data from 23 disciplines from 60 major research universities were analyzed in several phases. First, descriptive statistics and boxplots were calculated and constructed to determine the extent to which time-to-degree varied across departments within each discipline. Correlation matrices were constructed to identify significant relations between the independent variables and time-to-degree as well as important relationships among the independent variables. Next, independent variables values were compared across the first and fourth time-to-degree quartile departments in each discipline to further highlight the factors distinguishing the programs with the fastest and slowest time-to-degree. Finally, several multiple regression equations were computed to specify direct and indirect effects on time-to-degree in each discipline.;Generally, the results confirm the viability of the proposed theoretical model of departmental variation. The model works particularly well in the physical sciences where the adjusted R2s average over 0.58, but less well in the medical sciences, with an average of 0.42. While the specific variables predicting variation differed somewhat by discipline, the general model held. Research "climate", the degree to which department's relied on students to support themselves financially, and overall program quality emerged consistently as the strongest predictors of departmental variation in time-to-degree.;This study tested the proposition suggested by a proposed model that doctoral degree duration is determined by the direct and indirect effects of institutional characteristics, departmental attributes, student quality, and financial support patterns. |
