This dissertation explores the effect of simulation and the debriefing method of Debriefing for Meaningful Learning (DML) on diagnostic reasoning development in family nurse practitioner students (FNP-s) as measured by the diagnostic thinking inventory (DTI). A total of 13 FNP-s participated in this exploratory descriptive pilot study. All students completed both the pre-DTI survey prior to the start of the study, and the post DTI survey at the study conclusion followed by the Debriefing Assessment for Simulation in Healthcare-Student Version (DASH-SV) survey. Students participated in three urgent care simulations followed by the debriefing method of DML. The results of this study used mean comparisons in a repeated measure analysis given the small sample size. Dependent groups t tests revealed significant gains on the knowledge subscale but not on the flexibility items of the DTI, suggesting that the improvement in diagnostic thinking skills evidenced in this sample was due to the increase in knowledge gained from participation in the simulations and associated DML debriefings but not to any significant changes in the flexibility subscales. The effect of the simulations followed by DML method was also evaluated on reaction time (RT) indices. Although the total DTI scores did not show evidence of a significant improvement in time related to the RT to the diagnostic questions, the knowledge subscale of the DTI showed evidence of a significant improvement in RT. The observation that these FNP-s responded to the knowledge subscale of the DTI significantly faster after the intervention than before, provides additional evidence that suggests that the diagnostic knowledge of these FNP-s was improved by this intervention. Knowledge (non-analytic reasoning) was improved by participation in the simulations followed by DML as evidenced by improvement in knowledge decision efficiency (shorter RTs) in this subscale, however, there was not a similar improvement in the RTs in the overall total DTI scores or in the flexibility subscale. Overall scores on this debriefing method using the DASH-SV were positive. Simulation with the debriefing method of DML was found to significantly increase knowledge structure in this small sample of FNP-s
