Relationships Between Nurses’ Work System, Safety-Related Performance, and Outcomes: A Structural Equation Model

OBJECTIVES: We examined relationships between nurses’ work system, safety-related performance, and outcomes based on a modified Systems Engineering Initiative for Patient Safety model. METHODS: A cross-sectional survey was conducted with 408 nurses from 2 general hospitals. Data on work system factors (person, organization, environment, tools, and task), processes (safety-related performance), and outcomes (staff and clinical outcomes) were collected. Structural equation modeling was used to determine the relationships between nurses’ work system factors, safety-related processes, and outcomes. RESULTS: Structural equation modeling yielded a comparative fit index of 0.918, standardized root mean square residual of 0.055, and root mean square error of approximation of 0.054, indicating an acceptable model fit. The person factor had a significant positive direct effect on nurses’ safety-related performance, and significant negative direct and indirect effects on the clinical outcome. The organization factor had significant positive direct effects on nurses’ safety-related performance and staff outcome, and a negative indirect effect on the clinical outcome. The task factor had a significant positive direct effect on staff outcome. However, the environment and tools factors had no significant effects on safety-related performance or outcomes. CONCLUSIONS: The findings demonstrated the usefulness of the Systems Engineering Initiative on Patient Safety model to explain safety-related performance and outcomes, indicating differential effects of work system factors. Although the person factor significantly affected safety performance and clinical outcomes, the organization factor was the most influential component for promoting safety-related performance and staff and clinical outcomes. These results can be used to prioritize activities for patient safety.