Background: Among the hospital jobs, nursing is an example of jobs where a person spends many hours with patients. Nurses who do not have good general health will not be able to take effective care of patients. Therefore, this research was conducted with the aim of investigating the mediator role of job involvement in explaining the effect of professional ethics values and source of control on nurses' job performance.
Materials and methods: The research was descriptive and structural equation modeling. All the nurses working in the public hospitals of Tehran in 2021 formed the statistical population of the research, 300 people were selected from among them with the multi-stage cluster random sampling method and research tools included job performance questionnaire, locus of control questionnaire, professional ethics questionnaire, and the job involvement questionnaire. Descriptive statistics, correlation coefficient and path analysis with SPSS and AMOS statistical software were used for data analysis.
Results: Based on the results of this research, the proposed model of causal relationships between the mentioned variables had an acceptable fit. In general, in the proposed research model, the results showed that the source of control and the value of professional ethics are directly and indirectly related to job performance in nurses through job involvement (P<0.05). Also, the results showed that there is a significant relationship between internal and external sources of control with job engagement (P<0.05). This relationship between the value of professional ethics and job involvement in nurses was also significant (P<0.05).