Doctoral capstone projects take on many forms depending on the specific program and discipline. Some common types of capstone projects for PhD and professional doctorate programs include dissertations, theses, major research papers, comprehensive exams, portfolios, and practicum projects. Here are some representative examples of capstone projects across different fields to illustrate the depth and rigor required at the doctoral level:

In education PhD programs, candidates often complete major action research projects as their capstone. One such project analyzed how instructional practices in undergraduate statistics courses could be improved to better support student learning and achievement, especially for minority and first-generation students. The scholar conducted a comprehensive literature review on evidence-based teaching methods, designed and carried out her own quasi-experimental study comparing two different approaches over two semesters, and analyzed the resulting student assessment data. Her dissertation provided recommendations for updating the statistics curriculum based on her findings to enhance student outcomes.

In clinical psychology doctorates, the capstone typically involves an original research dissertation. One dissertation from a PsyD program explored correlations between early childhood trauma exposure and likelihood of developing certain mental health disorders later in life. The student utilized a large dataset from an ongoing longitudinal study and performed multivariate statistical analyses to investigate relationships between Adverse Childhood Experiences (ACEs) scores and later diagnoses of PTSD, depression, and substance use disorders. Her novel dissertation advanced understanding of long-term impacts of childhood adversity and informed clinical approaches to trauma-informed care.

For engineering PhDs, the capstone regularly takes the form of sponsored industrial research. One such project was completed in collaboration with a major aerospace manufacturer. The goal was to develop and test new composite materials that could withstand higher temperatures for use in next-generation jet engine components. The candidate designed and 3D printed test samples with various fiber architectures and resin formulations, subjected them to fatigue testing at escalating heat levels, and used microscopic analysis to examine how material structures degraded over time and failure points. Her detailed final thesis provided the sponsoring company with validated data to inform commercialization of stronger, lighter composites.

In nursing doctorates, the capstone usually involves implementation of an evidence-based practice change initiative. One DNP student worked with a large hospital to reduce surgical site infections (SSIs) among high-risk cardiac patients. Through a comprehensive program evaluation, she identified gaps in existing pre- and post-operative SSI prevention protocols. Her project entailed developing standardized best practices, an intensive nurse education program, and updated screening tools to ensure compliance. Rigorous pre- and post-intervention data collection and analysis demonstrated that her evidence-based process improvements led to a 30% reduction in SSIs in the target patient group.

Professional doctorates in business often feature a practicum focused on solving an organizational problem. For example, one DBA candidate partnered with a mid-sized manufacturing firm struggling with low employee retention, especially among millennial workers. Through surveys, interviews and focus groups, he performed a detailed assessment of factors driving turnover. His capstone described implementation of a comprehensive talent management strategy informed by his findings. This included revamped recruiting, onboarding and mentorship programs, as well as flexible benefits, tuition reimbursement, and leadership development initiatives. Six-month post-implementation data showed retention rates had risen 15% overall and doubled among younger employees.

Across fields, strong doctoral capstones showcase candidates’ mastery of advanced research skills and subject matter expertise. By tackling real-world problems, implementing evidence-based solutions, and rigorously evaluating outcomes, these projects demonstrate the independent investigative abilities and practical problem-solving competencies expected of terminal degree recipients. The depth and scale of analysis in the examples shared here exemplify the extensive original work required to earn a PhD or professional doctorate.