Setting the Next Vital Sign Observation Interval as a Learning Objective in Simulation-Based Nursing Education: A Prospective Exploratory Observational Study

<b>Background/Objectives:</b> Abnormal vital signs often precede in-hospital clinical deterioration, but little is known about how nurses decide when to recheck vital signs. We examined how nurse characteristics relate to the next vital sign observation interval after detecting abnormal values and how this decision could be used as a learning objective in simulation-based education. <b>Methods:</b> In this prospective exploratory observational study at a university hospital in Japan, twenty-seven nurses used a full-body patient simulator across three scenarios: normal, low-urgency, and moderate-risk (moderately abnormal vital signs according to National Early Warning Score 2 [NEWS2] risk bands). After each assessment, participants specified in hours the interval they considered appropriate for the next vital sign observation. Nurse characteristics included years of clinical experience, advanced life support (ALS) training, and prior experiences recognizing or responding to deterioration. Mann-Whitney U tests and multiple regression were used to explore univariate and adjusted associations. <b>Results:</b> In the low-urgency scenario, ALS training was associated with shorter intervals (median 1 h vs. 3 h; <i>p</i> = 0.04). In the moderate-risk scenario, univariate analyses showed shorter intervals among nurses with greater experience and among those with ALS training (both <i>p</i> < 0.01). In adjusted models for the moderate-risk scenario, years of experience and prior experiences of recognizing and responding to deterioration were independently associated with shorter intervals (all <i>p</i> < 0.05), whereas ALS training was not. <b>Conclusions:</b> The decision to shorten observation intervals appears to reflect experiential aspects of clinical judgment. Integrating "setting the next observation interval" as an explicit learning objective in simulation may help strengthen nurses' clinical judgment for early recognition of deterioration. As an exploratory, single-center study with a small sample and fixed scenario order, these findings should be interpreted cautiously and used to guide larger confirmatory studies and curricular design. This study was not registered.