Evidence-based reasoning: Results from an intervention

In two studies, we develop and evaluate an intervention focused on one significant challenge that undergraduate students have with evidence-based reasoning—reasoning about different evidence types. Our Evidence-Based Reasoning intervention teaches students about three common evidence types—comparative, correlational, and causal—often discussed in the popular press. In Study 1, using a within-subjects design, we find students' performance on an objective evidence-based reasoning (OEBR) measure to be significantly improved post-intervention (Cohen's d = 2.05). In Study 2, we add two open-ended measures to examine the effects of the intervention on students' evaluations of evidence-based conclusions. We again find students to perform significantly better on the OEBR measure (Cohen's d = 0.96), as well as on two open-ended conclusion evaluation tasks (Cohen's d = 0.97 and d = 0.69). Moreover, we find some of these benefits to persist on a delayed post-test, administered three weeks after intervention.