Biomedical Engineering Students Gain Design Knowledge and Report Increased Confidence When Continually Challenged with Integrated Design Projects

Abstract

Introduction: The undergraduate biomedical engineering (BME) curriculum should prepare students to confidently approach complex problems, as graduates will enter the workforce in an environment of rising healthcare costs, decreasing average life expectancy, and significant socioeconomic disparities in health outcomes. With this landscape, solutions to contemporary problems will require innovative thinking and groundbreaking medical technologies, suggesting that the future of BME will be increasingly design-oriented. Undergraduate BME curricula generally include laboratory and project components aimed at preparing students for senior capstone; however, students may begin capstone without the knowledge, skills, and confidence required for engineering design success. With these shortcomings in mind, we vertically integrated design experiences in our undergraduate BME curriculum and evaluated student design performance throughout.

Methods: Four engineering design project assignments were developed and integrated into sophomore- and junior-level BME laboratory courses, establishing a continuous design thread spanning the four years of the undergraduate BME curriculum. Through the sequence of projects, student teams worked to design (1) fracture fixation devices, (2) electromyogram-controlled motor assemblies, (3) compact spectrophotometers, and (4) programmable drug dosing devices. We developed a common instructional Design Module, organized around an adapted version of the FDA waterfall diagram, and used it in each course to build student understanding of the BME design process. By emphasizing different portions of the waterfall diagram in each course and varying student deliverables, we implemented a stepwise approach to building student design confidence. The set of design projects also intentionally target a multitude of skills relevant to design, including computer-aided design (CAD), computational modeling, iteration, prototyping, programming (LabVIEW and Python), hardware-software integration, and technical communication.

A mixed methods approach was employed to assess student knowledge, confidence, and achievement in design. A pre-/post-quiz (8 questions worth 10 points total) was used to assess student knowledge of design concepts and their application toward medical device design. Students self-reported their design confidence levels prior to the first design project and after each design project, and focus groups were held after design projects to assess student design confidence going forward. Students also rated how worthwhile and enjoyable they found each project using a reflection grid and reflected on the integration of prior coursework into their design projects. Finally, student design reports were scored by instructors using a rubric influenced by AAC&U VALUE Rubrics and the Informed Design Teaching and Learning Matrix. Students also self-reported design mastery via survey, and these responses were correlated to scores from the instructor rubric.

Results: Students engaged in 200-level and 300-level projects demonstrated knowledge gains of the BME design process after one project (p < 0.0001) and further knowledge gains after a second project (not statistically significant). In particular, students gained knowledge related to the waterfall diagram, design requirements and constraints, and verification and validation (p < 0.005 for each). In their reflections, students demonstrate cognizance of prior coursework knowledge that they have integrated into their designs, adding to the sought-after sense of curricular connectedness. After the completion of each project, students self-reported significant confidence gains in four major areas (p < 0.05 for each): (1) design process and approach, (2) working with hardware, (3) working with software and interfacing with hardware, and (4) communicating results. Focus group responses support the observed quantitative improvements in student design confidence. Finally, instructor scoring of student design reports indicates that design achievement and ability to communicate design improve as students progress through the curriculum; however, student self-assessment of design mastery does not correlate strongly with instructor scores.

Discussion: Active learning in undergraduate classrooms has been shown to improve performance, motivation, and communication skills among engineering students. By implementing and assessing hands-on engineering design project assignments at the sophomore and junior levels, we have improved student design knowledge, confidence, and achievement prior to capstone design. Future work will address limitations of student self-reporting of confidence levels and will investigate changes in the quality of capstone projects that could result from better prepared students.