TESTING EFFECT AND COMPLEX COMPREHENSION IN A LARGE INTRODUCTORY UNDERGRADUATE BIOLOGY COURSE

Abstract

Traditional undergraduate biology courses are content intensive, requiring students to understand and remember large amounts of information in short periods of time. Yet most students maintain little of the material encountered during their education. Poor knowledge retention is a main cause of academic failure and high undergraduate attrition rates. Characterizing strategies that support robust learning is critical for ensuring student success. One such strategy is testing effect, the observation that repeated testing can improve the fidelity and durability of retained knowledge more than an equal quantity of restudy. Numerous investigations have described the nature and boundaries of testing effect. Very few, however, have characterized its efficacy in actual classroom practice. The current study investigated whether repeated testing or repeated study affected student retention and understanding of complex biological concepts. The study was conducted in a large (~320 students) introductory biology class. All study conditions and assessments were required components of the course. Student retention of two fundamental molecular biology "big ideas" was targeted; (1) the relationship between genotype and phenotype, and (2) the relationship between gene expression and cell function. Students were randomly assigned to one of three repeated quiz or study conditions. For four weeks, students encountered various combinations of multiple-choice (MC) questions and review material related to big ideas 1&2 and/or unrelated lecture topics. Five weeks after the last quiz, all students completed identical MC final exam questions related to both big ideas. To determine the quality of "understanding" assessed by the MC questions, a subset of students also completed a short answer (SA) test prior to the final exam. Both question formats assessed the same knowledge (2 big ideas) at the same level (comprehension and application). Final exam performance supported the finding that repeated retrieval improves long-term retention of knowledge relative to repeated study. Novel to other previous work conducted at the undergraduate level, the current findings suggest that repeated testing affects student retention and understanding of sophisticated concepts. Careful design and analysis of parallel multiple-choice and short answer questions demonstrated that each can target and elicit similar qualities and types of knowledge.