Institutional factors such as module types, course formats and examination formats play a crucial role in shaping student progression and duration. However, empirical research on the specific impact of these programme design features on student duration is limited. This study aims to examine the influence of different types of courses on students' initial registration and participation in examinations, focusing on module types, course formats and examination forms. The analysis shows that curricular conditions can lead to delays in study duration, regardless of student performance. Making exam registration and participation more binding could help to reduce the number of long-term students and shorten the duration of study, although the impact on pedagogical goals needs to be further investigated.The data for this study are administrative records of two cohorts of social science bachelor programmes, "SoSci A" (N=282) and "SoSci B" (N=328), over eight semesters at a large German university. Both programmes allow students to register for exams manually, with a flexible option to postpone exams even after registration. The programmes "SoSci A" and "SoSci B" have comparable introductory, statistics and bachelor thesis modules with the same course formats and examination forms, with the exception of the statistics module. Although students in both programmes have to attend lectures given by the same lecturer, in "SoSci A" it consists only of lectures and an exam, while in "SoSci B" it includes optional lectures, seminars and exercises and is assessed by a project report. Mean comparisons were made to analyse differences in initial enrolment and initial participation in the modules, using the recommended semester of the model curriculum as a reference point for centering. The specialisation modules in "SoSci A" offer students a choice between written assignments and oral examinations. Differences between first-time registration and participation by examination form were also analysed using mean comparisons.The results suggest systematic differences in student behaviour between the module types in both programmes. First-time participation in examinations was more delayed than first-time registration. The introductory module was often taken in later semesters, which could lead to didactic challenges in other modules. The thesis modules showed less variation and fewer outliers, suggesting that students used more flexibility for their thesis work. Comparing the implementation of the statistics module between "SoSci A" and "SoSci B", "SoSci A" showed significantly more variation and a greater average delay compared to "SoSci B". More interactive courses, such as seminars and project work with assessment of project reports, are therefore associated with earlier registration and participation in exams than courses based solely on lectures and exams, even when the subject matter is the same. Project and research modules may promote student initiative, self-organisation and integration into the institution, resulting in shorter study times. With regard to examination forms, there were no significant differences in the mean delays for first registration or first participation between written assignments and oral exams in "SoSci A" specialisation modules.