Development of a Tool to Assess Interrelated Experimental Design in Introductory Biology

Diversifying laboratory assessment modes broadens engagement with practical competencies in life science students

Laboratory practicals in life science subjects are traditionally assessed by written reports that reflect disciplinary norms for documenting experimental activities. However, the exclusive application of this assessment has the potential to engage only a narrow range of competencies. In this study, we explored how multiple modes of laboratory assessment might affect student perceptions of learned skills in a life science module. We hypothesized that while a mixture of assessments may not impact student summative performance, it might positively influence student perceptions of different skills that varied assessments allowed them to practice. This was informed by universal design for learning and teaching for understanding frameworks. In our study, in a third-year Bioscience program, written reports were complemented with group presentations and online quizzes via Moodle. Anonymous surveys evaluated whether this expanded portfolio of assessments promoted awareness of, and engagement with, a broader range of practical competencies. Aspects that influenced student preferences in assessment mode included time limitations, time investment, ability to practice new skills, links with lecture material, and experience of assessment anxiety. In particular, presentations were highlighted as promoting collaboration and communication and the quiz as an effective means of diversifying assessment schedules. A key takeaway from students was that while reports were important, an overreliance on them was detrimental. This study suggests that undergraduate life science students can benefit significantly from a holistic assessment strategy that complements reports with performance-based approaches that incorporate broader competencies and allow for greater student engagement and expression in undergraduate modules.NEW & NOTEWORTHY This study suggests that undergraduate life science students can benefit significantly from a holistic assessment strategy that complements reports with performance-based approaches that incorporate broader competencies and allow for greater student engagement and expression in undergraduate modules.

Developing a faculty support program for fostering enriching undergraduate laboratory experiences under limited resource conditions

Meaningful pedagogical reform requires good faculty training and support programs. Such support is particularly valuable when colleges and universities are trying to bring research and inquiry into the laboratory curricula under resource-limited conditions. In this situation, it may help to extend the scope of the faculty support program to include training for practicing experimental techniques, sustainable networking opportunities, and a space to learn about pedagogical reforms. From this perspective, we share our experience about building a faculty development program for public college teachers who teach undergraduate biology in India. Though we designed the program for low-resource settings, the experiments curated could very well represent core biological concepts typically identified by the international community. The activities and overall design of the program can be useful for initiating pedagogical reform in any college/university where the traditional approach to biology laboratory instruction predominates, and high-end research is not easy to access.

Imagining, designing, and interpreting experiments: Using quantitative assessment to improve instruction in scientific reasoning

Effectively teaching scientific reasoning requires an understanding of the challenges students face when learning these skills. We designed an assessment that measures undergraduate student abilities to form hypotheses, design experiments, and interpret data from experiments in cellular and molecular biology. The assessment uses intermediate-constraint free-response questions with a defined rubric to facilitate use with large classes, while identifying common reasoning errors that may prevent students from becoming proficient at designing and interpreting experiments. The assessment measured a statistically significant improvement in a senior-level biochemistry laboratory course, and a larger improvement between the biochemistry lab students and a separate cohort in a first-year introductory biology lab course. Two common errors were identified for forming hypotheses and using experimental controls. Students frequently constructed a hypothesis that was a restatement of the observation it was supposed to explain. They also often made comparisons to control conditions not included in an experiment. Both errors were most frequent among first-year students, and decreased in frequency as students completed the senior-level biochemistry lab. Further investigation of the absent controls error indicated that difficulties with reasoning about experimental controls may be widespread in undergraduate students. The assessment was a useful instrument for measuring improvement in scientific reasoning at different levels of instruction, and identified errors that can be targeted to improve instruction in the process of science.

An introductory biology research-rich laboratory course shows improvements in students' research skills, confidence, and attitudes

As part of a wider reform to scaffold quantitative and research skills throughout the biology major, we introduced course-based undergraduate research experiences (CURE) in sections of a large-enrollment introductory biology laboratory course in a mid-level, public, minority-serving institution. This initiative was undertaken as part of the in the National Science Foundation / Council for Undergraduate Research Transformations Project. Student teams performed two or three experiments, depending on semester. They designed, implemented, analyzed, revised and iterated, wrote scientific paper-style reports, and gave oral presentations. We tested the impact of CURE on student proficiency in experimental design and statistical reasoning, and student research confidence and attitudes over two semesters. We found that students in the CURE sections met the reformed learning objectives for experimental design and statistical reasoning. CURE students also showed higher levels of experimental design proficiency, research self-efficacy, and more expert-like scientific mindsets compared to students in a matched cohort with the traditional design. While students in both groups described labs as a positive experience in end-of-semester reflections, the CURE group showed a high level of engagement with the research process. Students in CURE sections identified components of the research process that were difficult, while also reporting enjoying and valuing research. This study demonstrates improved learning, confidence, and attitudes toward research in a challenging CURE laboratory course where students had significant autonomy combined with appropriate support at a diverse public university.

An Active Learning Intervention Based on Evaluating Alternative Hypotheses Increases Scientific Literacy of Controlled Experiments in Introductory Biology

Scientific education provides a set of tools to make sense of a complex world by teasing out complicated cause-and-effect relationships, such as the elimination of effects of confounding factors in controlled experiments. There is evidence that depth of understanding of controlled experiments is lacking among undergraduate science students despite exposure to controlled experiments in courses. To examine the understanding of controlled experiments, we developed a two-tiered assessment that includes closed-ended and open-ended questions, with three types of questions, i.e., (i) a scientific scenario about a flawed drug study, (ii) an everyday-life scenario about flawed thinking regarding product effectiveness, and (iii) a direct question about explaining controlled experiments. Consistent with previous findings, we demonstrated that large percentages of students in introductory biology courses at both a research-intensive institution and a primarily undergraduate, minority-serving institution failed to recognize the need to account for confounds. Based on these findings, we tested the hypothesis that scientific literacy could be improved through a course-based intervention using an active learning framework focused on science as a process of evaluating alternative hypotheses. We found start-to-end-of-semester improvement in students' identification of unaccounted confounds with a scientific scenario in an intervention course but not in the control course. Interestingly, students in both the control and intervention courses showed improvement when tested with a scenario based on everyday life. The study findings suggest that a concerning number of college students may not account sufficiently for uncontrolled variables in real-life situations, and we present a widely applicable instructional strategy that improves on this broadly relevant scientific reasoning skill.

A course-based undergraduate research experience examining neurodegeneration in Drosophila melanogaster teaches students to think, communicate, and perform like scientists

As educators strive to incorporate more active learning and inquiry-driven exercises into STEM curricula, Course-based Undergraduate Research Experiences (CUREs) are becoming more common in undergraduate laboratory courses. Here we detail a CURE developed in an upper-level undergraduate genetics course at Yeshiva University, centered on the Drosophila melanogaster ortholog of the human neurodegeneration locus PLA2G6/PARK14. Drosophila PLA2G6 mutants exhibit symptoms of neurodegeneration, such as attenuated lifespan and decreased climbing ability with age, which can be replicated by neuron-specific knockdown of PLA2G6. To ask whether the neurodegeneration phenotype could be caused by loss of PLA2G6 in specific neuronal subtypes, students used GAL4-UAS to perform RNAi knockdown of PLA2G6 in subsets of neurons in the Drosophila central nervous system and measured age-dependent climbing ability. We organized our learning objectives for the CURE into three broad goals of having students think, communicate, and perform like scientists. To assess how well students achieved these goals, we developed a detailed rubric to analyze written lab reports, administered pre- and post-course surveys, and solicited written feedback. We observed striking gains related to all three learning goals, and students reported a high degree of satisfaction. We also observed significantly improved understanding of the scientific method by students in the CURE as compared to the prior year's non-CURE genetics lab students. Thus, this CURE can serve as a template to successfully engage students in novel research, improve understanding of the scientific process, and expose students to the use of Drosophila as a model for human neurodegenerative disease.

Self-Efficacy and Performance of Research Skills among First-Semester Bioscience Doctoral Students

Research skills, especially in experimental design, are essential for success in bioscience doctoral training. While there is a growing body of literature on the development of research skills among science, technology, engineering, and mathematics doctoral students, very little is specific to biosciences. We seek to address this gap by characterizing aptitude and self-perceived facility with research skills among incoming bioscience doctoral students, as well as how and why they change over the first semester of doctoral training. Our results reveal variability in research skills self-efficacy and a wide range in aptitude and self-perceived facility with experimental design at the beginning of the semester, both of which are uncorrelated with the duration of predoctoral research experience. We found that students significantly improved in both experimental design performance and research skills self-efficacy over their first semester; students attributed their experience and comfort with experimental design to a variety of factors, including laboratory research, course work, mentoring, and interaction with colleagues. Notably, we found that the largest research skills self-efficacy gains were aligned with material that was covered in students’ first-year course work about experimental design. Together, these results demonstrate the importance of explicit training in experimental design and other research skills early in bioscience doctoral training.

Increased Scaffolding and Inquiry in an Introductory Biology Lab Enhance Experimental Design Skills and Sense of Scientific Ability

We present a model for the process of redesigning the laboratory curriculum in Introductory Organismal Biology to increase opportunities for meaningful inquiry and increase student recognition of their scientific skill development. We created scaffolded modules and assignments to allow students to build and practice key skills in experimental design, data analysis, and scientific writing. Using the Tool for Interrelated Experimental Design, we showed significantly higher gains in experimental design scores in the redesigned course and a more consistent pattern of gains across a range of initial student scores compared with the original format. Students who completed the redesigned course rated themselves significantly higher in experimental design, data collection, and data analysis skills compared with students in the original format. Scores on the Laboratory Course Activity Survey were high for both formats and did not significantly differ. However, on written course evaluations, students in the redesigned course were more likely to report that they engaged in "real science" and their "own experiments." They also had increased recognition of their specific analytical and writing skill development. Our results demonstrate that intentional, scaffolded instruction using inquiry modules can increase experimental design skills and sense of scientific ability in an introductory biology course.