Associations between hospital ethical climate, moral sensitivity and nurses’ ethical behaviour: a cross-sectional study and mediation analysis

Background Ethical behaviour is a cornerstone of high-quality nursing care. However, the mechanisms through which organisational environment is associated with individual ethical action remain underexplored. ‌This study aimed to examine the mediating role of moral sensitivity in the relationship between hospital ethical climate and nurses’ ethical behaviour within the framework of Social Cognitive Theory. Method A cross-sectional, quantitative study was conducted from March to April 2025. 691 nurses at the First Affiliated Hospital of Ningbo University were invited to participate, and 607 completed valid questionnaires, forming the final sample. Data were collected using the demographic information questionnaire, Chinese-version Hospital Ethical Climate Survey, Moral Sensitivity Questionnaire-Revised, and Nurses’ Ethical Behaviour Scale. Data analysis was performed using SPSS 26.0 and Hayes’ PROCESS Model 4, employing descriptive statistics, Pearson correlation analysis, and a bootstrap mediation analysis with 5,000 resamples. Results Hospital ethical climate was positively correlated with ethical behaviour ( r = 0.45, p < 0.001) and moral sensitivity ( r = 0.44, p < 0.001); moral sensitivity was also positively associated with ethical behaviour ( r = 0.31, p < 0.001). Moral sensitivity partially mediated the relationship between hospital ethical climate and ethical behaviour, with a statistically significant indirect effect ( B = 0.051, 95% CI [0.018, 0.085], p = 0.002), which accounted for only 13.7% of the total effect, indicating that other unmeasured factors likely are associated with ethical behaviour. Conclusion Moral sensitivity played a significant yet limited partial mediating role in the relationship between hospital ethical climate and nurses’ ethical behaviour, with the direct pathway accounting for 86.3% of the total effect. These findings align with the core tenets of social cognitive theory, supporting the interconnections among organizational factors, moral sensitivity as a cognitive factor, and nurses’ ethical behaviour. This provides preliminary cross-sectional empirical support for one component of the broader framework of reciprocal determinism in nursing ethics contexts. Nursing managers may consider targeted improvement of the hospital ethical climate as a potential core strategy, complemented by moral sensitivity training, as a promising approach to supporting better ethical practice and clinical care quality. However, the actual effectiveness of this combined intervention remains to be systematically verified through future prospective intervention studies.