Research in Higher Education

, Volume 59, Issue 5, pp 529–552 | Cite as

How to Increase PhD Completion Rates? An Impact Evaluation of Two Reforms in a Selective Graduate School, 1976–2012

  • Koen Geven
  • Jan Skopek
  • Moris TriventiEmail author


Graduate and doctoral schools around the world struggle to shorten the long time to degree and to prevent high dropout rates. While most of previous research studied individual determinants of PhD completion, we analyze the impact of two structural reforms of the doctoral program on thesis completion at a selective European graduate school. Exploiting a unique PhD dataset covering 30 entry cohorts, we identify reform effects on PhD outcomes using an interrupted time-series regression design. We find that the first reform improved timely completion rates by between 10 and 15 percentage points (according to the specific outcome), whereas the second reform increased completion rates by between 9 and 20 percentage points. Additionally, each reform reduced dropout rates by 7 percentage points. The results are robust to various sensitivity checks. At the end, we discuss lessons learned for those in charge of graduate schools and/or PhD programs.


Doctoral program Time-to-degree Attrition Dropout Interrupted time-series analysis 



We would like to thank the European University Institute for providing us with the data and Ken Hulley for precious guidance on the information contained in the dataset. We would like to thank the participants to our seminar at the EUI’s Economics Department (2015) and at the COMPIE Conference at the Catholic University of Milan (2016) for useful comments. We would also like to express our gratitude to Hans-Peter Blossfeld, Andrea Ichino, Michael Grätz, Hannes Kröger, Loris Vergolini, and Nadir Zanini, as well as two reviewers who provided stimulating remarks on a previous version of this article. All remaining errors are our own.


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Copyright information

© Springer Science+Business Media, LLC 2017

Authors and Affiliations

  1. 1.World BankWashingtonUSA
  2. 2.Department of Sociology, School of Social Sciences and Philosophy, Trinity College DublinThe University of DublinDublin 2Ireland
  3. 3.Department of Sociology and Social ResearchUniversity of TrentoTrentoItaly

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