Investigating undergraduate health sciences students' acceptance of evolution using MATE and GAENE

Background: Despite the overwhelming agreement among scientists regarding the fundamental importance of evolution to all areas of biology, a lack of evolution understanding and acceptance has been reported in studies of students, educators, and members of society. In the present study, we investigate and report evolution acceptance in a population of undergraduate health sciences students enrolled in a first-year foundational biology course. Two published instruments - The Measure of Acceptance of the Theory of Evolution (MATE) and the Generalized Acceptance of Evolution Evaluation (GAENE) - were used to quantify evolution acceptance. A confirmatory factor analysis (CFA) was performed on both instruments to test whether the items measured the underlying construct sufficiently. Additionally, Rasch scaling was used to investigate fit between the data and the measurement model, and to determine if the MATE should be treated as a unidimensional or bidimensional instrument. Using correlation and regression analysis, we examined the relationships between the two measures of evolution acceptance, and between measures of evolution acceptance with other student variables of interest. Results: The health sciences students in this study demonstrated high acceptance of evolution at the start of term, as well as a significant increase in evolution acceptance from pre- to post-test. CFA and Rasch scaling provided some evidence that the MATE is a bidimensional instrument, but considering MATE as a bidimensional instrument provided little additional insight compared to treating MATE as a unidimensional instrument. Measures of evolution acceptance resulting from the MATE and GAENE instruments were significantly and strongly correlated. Multiple regression modeling identified underrepresented minority status as a demographic variable predictive of evolution acceptance, and provided further evidence of the strong association between the MATE and GAENE instruments. Conclusions: The undergraduate health sciences students in this study demonstrated a significant increase in evolution acceptance from pre- to post-test after one semester of instruction in general biology. Measures of evolution acceptance from the MATE and GAENE instruments were strongly correlated whether MATE was treated as a unidimensional or bidimensional instrument. This work provides initial indications that the MATE and GAENE instruments perform comparably as measures of evolution acceptance. Although the instruments are closely related, this work found more psychometric evidence for interpreting and using GAENE scores than MATE scores as a measure of evolution acceptance.