BackgroundCritical thinking has been identified as one of the standards for nursing school accreditation and a long-standing outcome of nursing education and nursing practice. High-fidelity simulation is one method currently used by nursing programs to increase critical thinking in nursing students. Despite these expectations, there is limited empirical evidence which compares the effects of simulation to other teaching strategies. ObjectivesThe purpose of this study was to examine whether statistically significant differences existed in mean critical thinking skill scores within groups (pretest to posttest) and between groups (simulation versus written case studies). DesignA quantitative causal-comparative methodology with a pretest/posttest design. SettingA private university in the midwestern United States which offers a four-year Bachelor of Science Nursing program. ParticipantsBaccalaureate junior nursing students (N = 69) were recruited from a convenience sample and divided into two groups which consisted of a simulation group (n = 36) and a written case studies comparison group (n = 33). MethodsThis research study consisted of a pretest, three weeks of being in either the simulation group or the written case studies group, and a posttest. The Health Science Reasoning Test (HSRT) was the instrument used for the pretest and posttest to measure critical thinking skills of all participants. ResultsA repeated measures mixed analysis of variance (ANOVA) indicated there was no statistically significant difference in participants' mean critical thinking scores within groups (pretest to posttest) or between groups (simulation versus written case studies). ConclusionsThe use of high-fidelity simulation as a teaching strategy versus written case studies to increase critical thinking skills of nursing students was not supported.