Tools for Assessment in Genetics: Making Instruments to measure student understanding of genetics co

Nancy Boury
Assistant Professor
Iowa State University

Genetics concepts are at the very heart of modern biology, particularly in inheritance, evolution, species variation, and gene function and therapy, and therefore, act as a gateway to a deeper understanding of biology as a whole. These topics tend to be challenging and students enter college with a diversity of background knowledge and misconceptions. An important facet of teaching genetics in an evidence-based fashion is identifying which teaching methods are most effective in a given context. While there are large, broadly-focused concept inventories in genetics (GCA), smaller, more focused inventories would allow instructors to quickly identify and remedy student mistakes and to tailor learning activities to resolve prior knowledge deficiencies. Using the same, short, validated assessment will also enable educators to calculate learning gains and determine the relative effectiveness of different teaching techniques when used pre- and post-instruction.

Guiding Questions
1) When making a criterion referenced assessment, how can we determine if student multiple choice responses capture the misconceptions they were designed for?
2) What are the common misconceptions students hold about mutations, pedigree analysis, and epistasis?

• We created a new concept inventory construction step and used it with mutations, pedigree analysis, and epistasis concept inventory validation. While internal consistency measures (e.g. KR-20) and item-descriptors (e.g. item difficulty) are standard methods to determine the validity and reliability of a criterion referenced test, these are measures are indirect. We worked with a statistician and psychometrician to combine qualitative analyses with statistical testing to form a novel confirmatory test: congruence testing.
• The Tools for Assessment in Genetics (TAG) group has created and validated 3 criterion referenced assessments (CRA). These probe students’ understanding of mutations, pedigree analysis, and epistasis and are in the process of being published or in the manuscript writing stages.
• Our research group has presented these data at SABER, ASMCUE, and ASBMB meetings.

Broader Impacts
• This project benefits society by providing the tools to education researchers and educators that are needed to document effective learning. According to the College Board, there are 1695 different colleges offering biology majors in the United States as well. Each of these curricula requires both general biology and general genetics in their program of study. This means there are approximately 100,000 students enrolled in general genetics undergraduate courses in the United States alone.
• As a result of this project, we have produced 3 separate criterion referenced assessments based on core concepts established by the Genetics Society of America (GSA). We have submitted the papers describing mutations and pedigree analysis instruments and plan to submit a detailed description of mutations misconceptions and the epistasis concept inventory paper this summer.
• This project also advanced how concept inventories are validated. Congruence testing is a method that provides the first direct evidence that the instrument items (question and answers) reflect the misconceptions they were designed to capture.


Rebecca Seipelt-Thiemann