* Program requirements: Different universities have varying requirements for coursework, exams (e.g., comprehensive exams), and the dissertation. Some programs may be more rigorous or demand more extensive research.
* Dissertation research: The length of time spent on research and writing the dissertation is highly variable, depending on the topic's complexity, the availability of resources, and the student's research progress. This is often the most significant factor determining the overall timeframe.
* Funding: Securing funding (fellowships, assistantships, etc.) can impact the timeline, as teaching or research duties associated with funding can add to the overall workload.
* Student's pace: Individual students work at different speeds. Some are faster writers and researchers, while others need more time to develop their ideas and complete their work.
Therefore, while 5-7 years is a common range, it's crucial to understand that it's an estimate, and individual experiences can vary considerably.